CIVIL SERVICE EXAM PREPARATION NOTES: SCIENCE AND TECH CONCEPTS

SCIENCE AND TECH CONCEPTS

OSMOSIS

In osmosis solvent molecules moves from low concentration solution to higher concentration solution through a semipermeable membrane.

In reverse osmosis external pressure is applied to the higher concentration solution. Solvent in this case move from concentrated solution to dilute solution. External pressure applied is above the osmotic pressure.

remember this diagram to remember the concept

SUPERCOMPUTER

A supercomputer is a computer with a high-level computational capacity compared to a general-purpose computer. Performance of a supercomputer is measured in floating-point operations per second (FLOPS)

As of June 2016 the fastest supercomputer in the world is the Sunway TaihuLight, with a Linpack benchmark of 93 PFLOPS, exceeding the previous record holder, Tianhe-2, by around 59 PFLOPS.

The Green500 list ranks computers from the TOP500 list of supercomputers in terms of energy efficiency, typically measured as LINPACK FLOPS per watt
PARAM Yuva[edit]

PARAM Yuva belongs to the PARAM series of supercomputer developed by the Centre for Development of Advanced Computing. It is capable of performing at about 54000 gigaflop/s or 54 teraflop/s.

CLOUD COMPUTING

Cloud Computing simply means the practice of using a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer.

An example would be using Dropbox , where all your information is saved remotely on the cloud and available from anywhere.

Cloud computing provides optimum use of resources. This is because unused resources such disk space, CPU etc are sold or provided in smaller units to large number of users.

Cloud computing provides higher degree of privacy and security over conventional methods is incorrect. The biggest issue with cloud computing is that since you do not own a separate server or resource but are merely sharing a part of the resource which is being shared with a large number of users, privacy concerns remain. Think of it like having your own office/flat, vs having a shared office/ shared flat with another organisation/people. Having one’s own office/flat offers more privacy as compared to having a shared office/flat.

Cloud Computing reduces the cost of infrastructure for end users . You only pay for what you use and costs are brought down

THYMOSIN

The thymus gland, located behind your sternum and between your lungs, is only active until puberty.

After puberty, the thymus starts to slowly shrink and become replaced by fat.
Thymosin is the hormone of the thymus, and it stimulates the development of disease-fighting T cells.

The thymus gland will not function throughout a full lifetime, but it has a big responsibility when it’s active—helping the body protect itself against autoimmunity, which occurs when the immune system turns against itself. Therefore, the thymus plays a vital role in the lymphatic system (your body’s defense network) and endocrine system.

Before birth and throughout childhood, the thymus is instrumental in the production and maturation of T-lymphocytes or T cells, a specific type of white blood cell that protects the body from certain threats, including viruses and infections. The thymus produces and secretes thymosin, a hormone necessary for T cell development and production.

The thymus is special in that, unlike most organs, it is at its largest in children. Once you reach puberty, the thymus starts to slowly shrink and become replaced by fat. By age 75, the thymus is little more than fatty tissue. Fortunately, the thymus produces all of your T cells by the time you reach puberty.

1. Consider the following statements on Global Positioning System (GPS):

1. GPS allows accurate time-stamping on ATM transactions.

2. GPS relies on a set of satellites for transferring signals worldwide.

Which of the above statements is/are correct?

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

2. Some species of which of the following kinds of organisms can act as agent for controlling pests and diseases in agriculture?

1. Bacteria

2. Viruses

3. Fungi

Choose the correct alternative using the codes given below.

(a) 2 and 3 only

(b) 1 and 3 only

(d) 1, 2 and 3

3. Parasitism is a symbiotic relationship where one species, the predator, benefits at the expense of the other, the host. Some species of which of the following act as predator in various parasitic relationships?

1. Plants

2. Birds

3. Butterflies

Choose the correct alternative using the codes given below.

(a) 1 and 2 only

(b) 1 and 3 only

(d) 1, 2 and 3

4. Among the following, which one does not belong to the phyla of other three?

(a) Prawn

(b) Shrimp

(d) Squid

5. Which of the following is/are among the known ways of transmission of Zika virus?

1. Mosquito bites

2. Blood Transfusion

3. Contaminated needles

4. From a mother to her foetus

Choose the correct alternative using the codes given below.

(a) 1 and 4 only

(b) 1, 2 and 4 only

(d) 1, 2, 3 and 4

6. Recently, ‘bacteriophages’ were in news. What are they?

(a) bacteria that combine with algae and can be use to contain oil spills

(b) fungi that can be used to replenish the degraded soils

(d) bacteria that become toxic to other bacteria under specific conditions

7. What are ‘Exoplanets’?

(a) large sized asteroids believed to be the remnants of a primitive planet

(b) planets orbiting stars outside the solar system

(d) planets orbiting stars in other galaxies

8. The warming effect of sun rays is due to the

(a) ultra violet part of the sunlight

(b) visible part of the sunlight

(d) ultra violent and infrared part of the sunlight

9. Some organisms like yeast obtain energy through anaerobic respiration during which the glucose breaks down to produce energy along with

(a) lactic acid, carbon dioxide and water

(b) water and carbon dioxide

(d) water and lactic acid

10. Which of the following diseases is/are caused by bacteria?

1. Anthrax

2. Malaria

3. Polio

Choose the correct alternative using the codes given below.

(a) 1 only

(b) 2 and 3 only

(d) 1, 2 and 3

11. Which of the following is/are among the ‘micro-elements’ required for plant growth?

1. Copper

2. Zinc

3. Potassium

4. Sulphur

5. Manganese

Choose the correct alternative using the codes given below.

(a) 1, 2 and 5

(b) 2, 3, 4 and 5

(d) 1, 2, 3, 4 and 5

12. Which of the alternative represents the correct order of the food chain with the following organisms?

(a) Krill – Algae – Seals – Orca

(b) Algae – Seal – Krill – Orca

(d) Algae – Krill – Seals – Orca

13. Consider the following statements?

1. Vitamins assist the body in utilizing the nutrients.

2. Vitamins help in transporting the minerals to required places.

3. No vitamin can be synthesized in the body.

Choose the correct alternative using the codes given below.

(a) 1 and 2 only

(b) 2 only

(d) 1, 2 and 3

14. Which of the following diseases is/are among the vaccine preventable diseases to be covered under the Mission Indradhanush?

1. Polio

2. Measles

3. Hepatitis C

4. Tuberculosis

Choose the correct alternative using the codes given below.

(a) 3 and 4 only

(b) 1, 2 and 3 only

(d) 1, 2, 3 and 4

15. Consider the following statements:

1. Neutrinos are massless particles filling up most of the empty space.

2. They are easy to detect as they can be deflected even by weak forces like gravity.

Which of the above statements is/are correct?

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

16. Which of the following diseases are caused due to the deficiency of Vitamin C ?

1. Scurvy

2. Night Blindness

3. Rickets

Choose the correct alternative using the codes given below.

(a) 1 only

(b) 1 and 2 only

(d) 1, 2 and 3

17. Certain microbes are called ‘superbugs’ because

(a) of their high rate of prevalence

(b) of their ability of transmission across species

(d) of the very long period of medication they require

18. The National Biotechnology Development Strategy unveiled in December last entails launching of mission across which of the following sectors?

1. Food and Nutrition

2. Education

3. Healthcare

4. Clean Energy

5. Human Capital

Choose the correct alternative using the codes given below.

(a) 2, 3, 4 and 5

(b) 1, 2, 3 and 4

(d) 1, 2, 3, 4 and 5

19. Consider the following statements:

1. Biotechnology Industry Research Assistance Council (BIRAC) is a not-for-profit Public Sector Enterprise.

2. It has been set up by the Department of Scientific and Industrial Research as an interface agency to empower emerging biotech enterprises.

Which of the above statements is/are correct?

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

20. What is Spaceward Bound Programme?

(a) It is an inter-governmental project that funds expeditions to deep space

(b) It is a NASA project that funds expeditions to places with extreme climate conditions

(d) It is a JAXA project that funds expeditions to discover habitable planets outside the solar system

21. What is SAMAR?

1. A system to monitor the concentration of aerosols and black carbon in the atmosphere.

2. It has been launched by Indian Meteorological Department.

Which of the above statements is/are correct?

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

22. Consider the following statements:

1. Micro-propagation is the practice of multiplying plants using modern techniques like tissue culture.

2. It is used to multiply novel plants like genetically modified ones.

Which of the above statement(s) is/are correct?

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

23. Consider the following statements :

Cellular Technology evolves in stages called Generation (G), where

1. A Generation represents the number of subscribers, higher Generation has more subscribers.

2. 2G technology has CDMA standard and 3G has GSM standard.

Which of the above statement(s) is/are correct?

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

24. Which of the following is/are correct matched?

1. Cassini – Huygens : Jupiter

2. New Horizons : Neptune

3. Dawn : Saturn

Choose the correct alternative using the codes given below.

(a) 3 only

(b) 1 and 2 only

(d) None

25. Which of the following is/are genetic disorders?

1. Thallasemia

2. Haemophilia

3. Colour blindness

Choose the correct alternative using the codes given below.

(a) 2 and 3 only

(b) 1 and 2 only

(d) 1, 2 and 3

Q.1) Consider the following statements:
1. ELISA test is employed as the first and most basic test for an individual to detect cancer.
2. Almost 50% of human beings have RH (+ve) blood while the remaining have Rh(-ve) blood.

Select the correct statement using the codes given below.
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Ans-d

Explanation– Elisa means Enzyme-linked immunosorbent assay. It is very very sensitive test to detect antigen or antibodies in the blood/serum. We use enzyme –substrate reaction and the color change due to it as a process to identify antigen or antibody in it. It is very powerful method and can give presence of protein present even in picograms.

Antigens are infectious agents and their materials inside body. This causes body to produce antibodies to fight against them. If we can detect type of antibody in blood or serum we may detect what kind of antigen is there. Elisa comes thus here as very handy in it.

Elisa is not the basic test of cancer. It is basic test of HIV. So statement 1 is wrong.

You can read about cancer detection tests here.

Q.2) Consider the following vegetables. Which of the following are the roots used as vegetables?
1. Potato
2. Radish
3. Turnip
4. Yam

Select the correct answer using the codes given below.
a) 1, 2 and 3 only
b) 2, 3 and 4 only
c) 2 and 4 only
d) 1 and 3 only

Ans- b

Explanation-Potato is a stem tuber. Tubers are parts of plants which stores food. Thus Statement 1 is wrong.

Turnip is a root. You can read more here.

Radish is a root. You can read more here.

Yam is also a root tuber.

Hence option b

Q.3) In which of the following sets of blood groups, blood transfusion is possible?
a) A and O (A donor)
b) B and A (B donor)
c) A and AB (A donor)
d) AB and O (AB donor)

Ans- c

Explanation– Blood group O is universal donor and AB is a universal recipient. Being a universal donor, Blood group O can donate blood to all other groups and being a universal recipient blood group AB can accept blood from all other groups.

Thus in all the options, c is the one in which transfusion is possible as AB will receive and A will donate

Q.4) Consider the following plants:
1. Jasmine
2. Sugarcane
3. Turmeric

Which of the above is/are propagated by vegetative method?
a) 1 only
b) 1 and 2 only
c) 2 and 3 only
d) 1, 2 and 3

Ans-d

Explanation–Vegetative propagation or vegetative reproduction is the process of multiplication in which a portion of plant body functions as propagates and develops into a new individual without any sexual union or fertilization. All three options can be grown like this.See here

Q.5) Consider the following statements:
1. Dengue is a protozoan disease transmitted by mosquitoes.
2. Retro-orbital pain is not a symptom of Dengue.
3. Drastic Decline in number of blood platelets is found in patients suffering from dengue.

Select the correct statement using the codes given below:
a) 1 and 2 only
b) 3 only
c) 2 and 3 only
d) 1 and 3 only

Ans- b

Explanation-Dengue is caused by dengue virus. It is malaria which is caused by protozoa. Thus, statement 1 is wrong.

Retro orbital pain or pain behind the eyes is one of the symptom of Dengue. See here. Statement 2 is wrong.

Dengue is disease in which platlets get greatly reduced. Thus statement 3 is correct.

Q.6) In the case of a ‘test-tube baby’?
a) fertilization takes place inside the test tube
b) development of the baby takes place inside the test tube
c) fertilization takes place outside the mother’s body
d) unfertilized egg develops inside the test tube

Ans– c

Explanation– A test tube baby is the term that refers to a child that is conceived outside the woman’s body. The process is also referred to as “in vitro” (outside the body) fertilization

Q.7) Which one of the following is the most important characteristic of water to act as a good solvent?
a) Purity of water
b) Ionizing power of water
c) Polar nature of water
d) Dissolving power of water

Ans- c

Explanation- This is because of polar nature of water molecule. Water molecule has uneven distribution of electron density. Water has a partial negative charge near the oxygen atom due the unshared pairs of electrons, and partial positive charge on hydrogen atoms. This makes it polar and it is able to act as a good solvent

Q.8) Which of the following statements regarding carbon dioxide is/are correct?
1. It is prepared on large scale by the action of water on lime.
2. In the solid form it can be used as a refrigerant.

Select the correct answer using the codes given below.
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Ans– b

Explanation– Carbon dioxide is prepared on the large scale by heating of calcium carbonate at 850 degree celcius. Action of water on lime produces calcium hydroxide. Statement 1 is wrong.

Carbon dioxide is used as a refrigent under name dry ice

Q.9) Sulphuric acid is used in the manufacture of:
1. Fertilizers
2. Dyestuff intermediates
3. Pigments and paints
4. Storage batteries

Select the correct answer using the codes given below:
a) 1 and 2 only
b) 2 and 3 only
c) 1, 3 and 4 only
d) 1, 2, 3 and 4

Ans-d

Explanation– Sulphuric acid is known as king of all chemicals because of wide applications of it. All options find use of it.See this. Sulphuric acid is used as an important ingredient in textile dyes and in leather industry dyes

Q.10) Which of the following statements is/are true regarding a light wave travelling from air to glass?
1. Its frequency remained unchanged.
2. Its speed changes.

Select the correct answer using the codes given below.
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Ans–c

Explanation– This is process of refraction being talked about. In refraction speed and wavelength of light changes as shown here. Frequency remains unchanged. This is because the electric and magnetic fields have to remain continuous at the refractive index boundary.

Q1. Which of the following have been the reasons for opposition to Bt crops in India?

Bt crops have been created by inserting a gene from soil bacteria into its genome
There is a feeling that Bt toxin may get activates in the body and may cause leaky gut syndrome.
The seeds of Bt crops such as Bt Brinjal are terminator seeds and require buying seeds every season again and again
Introduction of Bt crops may affect bio diversity

Which of the above statements are correct?

(a) 1 and 2 only
(b) 1, 2 and 4 only
(c) 1, 3 and 4 only
(d) 1, 2, 3 and 4 only

Ans– b

Explanation-

Statement 1 is correct. Bt means Bacillus thuringiensis which is a gram positive soil dwelling bacteria. See here.

Statement 2 is correct Bt toxins harms the digestive system by effectively attacking normal gut cells and making holes in the intestines. This can cause problems such as leaky gut syndrome. See here

Statement 3 is wrong. It is just a myth which is not proven yet for case of Bt brinjal. Seethis Hindu article.

Statement 4 is correct as Bt crops can affect Bio-diversity

Q2) In contxt of Multiple Drug Resistant bacteria, consider the following statements

Improper use of antibiotics leads to the rise of MDR Bacteria
MDR Bacteria only harms those people who make improper use of antibiotics
MDR is a concern because very little advances have been made in invention of newer anti biotics.

Which of the above statements are correct?

(a) 1 only
(b) 1 and 2 only
(c) 1 and 3 only
(d) 1, 2 and 3 only

Ans-c

Explanation- Statement 1 is right. Improper use of antibiotics lead to rise of MDR bacteria as it becomes resistant to it.

Statement 2 is wrong as MDR bacteria can affect anyone.

Statement 3 is true as this is becoming one of the biggest challenge of health industry.Check here

Q3) Consider the following statements

Blue color of the sky is due to the process of refraction of light.
The ocean looks blue because red, orange and yellow (long wavelength light) are absorbed more strongly by water than the blue color.

Select the correct statements from the choices given below –

a) 1 only
b) 2 only
c) Both 1 and 2.
d) Neither 1 Nor 2

Ans- b

Explanation- Blue color of the sky is due to the scattering of the light. This youtube video explains it brilliantly this process. Statement 1 is wrong thus as it is talking about refraction.

https://www.youtube.com/watch?v=qP2Vp1zj8H0

Statement 2 is correct. Particular color of the object is due to the reflection of that color from it. Rest colors are absorbed by this. Ocean water absorb red orange and yellow. Check this scientific American link.

Q4) With reference to pesticides and insecticides, consider the following statements :

1. Both pesticides and insecticides kill by poisoning, suffocating or paralyzing
2. Pesticides are a subgroup of insecticides that are specifically used for killing pests

Which of the statements given above is/are correct?

a) 1 only
b) 2 only
c) Both 1 and 2
d) Neither 1 nor 2

Ans-a

Explanation- Statement 1 is right as action mechanism of insecticide and pesticide work through by poisoning, suffocating or paralyzing only.

Statement 2 is wrong. Insecticides are subgroups of pesticides and not vice versa. Check this.

Q5) There are four fundamental forces in the universe

1. Gravitational force

2. Electromagnetic force

3. Strong nuclear force

4. Weak nuclear force

Arrange these forces in the order from strongest to weakest using the following codes:

a) 3,1,2,4
b) 3,2,1,4
c) 3,2,4,1
d) 3,4,1,2

Ans- c

Explanation- Decresing order of arrangement of forces are:

The Strong ForceResponsible for binding of nuclei. It is the strongest force in nature. This force is so strong that it binds and stabilize the protons of similar charges within a nucleus. However, it is very short range.
The Electromagnetic Force
Force between particles which have an electric charge. For example, negatively chared electrons bind nucleus of an atom, due to the presence of positively charge protons. The force is long range, in principle extending over infinite distance. However, the strength can quickly diminishes due to shielding effect.
The Weak Force This force is responsible for beta decay and other other decay processes involving fundamental particles. The range of this force is smaller than 1 fm and is 10-7 weaker than the strong force.

The Gravitational Force
Force which holds us onto the Earth is gravitational force. On the scale of atomic world it is of negligible. Gravitational force can extended to infinity. Larger the body the stronger the gravitational force. But on the scale of individual particles, the force is extremely small, in the order of 10-38times that of the strong force.

Q6) Recombinant DNA technology allows genes to be transferred

1. Across different species of plant

2. From animals to plants

3. From microorganisms to higher organisms

Select the correct answer using the codes given below:

a) 1 only
b) 2 only
c) 1 and 3 only
d) 1, 2 and 3

Ans- d

Explanation- Statement 1 is correct. As you can see in this, donor and receiver are different species of plants.

Statement 2 is correct. As this article says,

“In 1953, scientists discovered the structure of DNA, and in 1972, researchers developed a method for cutting and splicing DNA. That method became known as recombinant DNA, or rDNA, because it enabled scientists to cut and recombine segments of DNA. Since then, researchers have learned how to move genetic material in the form of DNA from one plant or animal to another. They can also take DNA from an animal and place it in a plant, and vice versa.”

Above link proof statement 3 is correct too

Q7) Brazil is considered to be the world’s first sustainable biofuel economy where ethanol is

used to fuel cars. It is derived from

a) potatoe
b) rice
c) wheat
d) sugarcane

Ans– d

Explanation– Brazil is considered to be the world’s first sustainable biofuels economy. Ethanol for fuel is obtained from the fermentation of the sugarcane. You can read it here

Q.1) If both husband and wife have blood group A, then their child cannot have which of the following blood group?a) A
b) O
c) AB
d) None

Ans- [C]

Explanation-

Blood Group	Antigen
A	Has only A antigen on red cells (and B antibody in the plasma)
B	Has only B antigen on red cells (and A antibody in the plasma)
AB	Has both A and B antigens on red cells (but neither A nor B antibody in the plasma)
O	Has neither A nor B antigens on red cells (but both A and B antibody are in the plasma)

Blood group is determined by the antigen present on RBC. As you can see, blood group A has only antigen A on RBCs. Therefore, baby of both the parents will either have antigen A on its blood cells or no antigen on it because antigen B is absent in both the parents.

Thus, either it will have blood group A or O. It can not have blood group B or AB.

Q.2) Bio-digester toilets are hailed as a solution to many of our problems. Which of the following statements about bio-digester toilets is correct?

They use aerobic bacteria
They require no or very low maintenance
They use less water

Select the correct statement using the codes given below.
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2 and 3

Ans- [ C]

Explanation– Biodigester toilets use anaerobic bacteria like Clostridium and Methanosarcina. Anaerobic bacteria don’t need oxygen to carry out biochemical reactions. They were found in Antarctica when DRDO sent scientists under India’s 13th Antarctic Mission in 1994 to look for microorganisms that can break down excreta. This was required for the military posted in higher altitude snow covered areas where deep pits were dug out and all excreta was collected. Afterwards it was dropped in plains or incinerated which required labor, cost and did pollution. Biodigester solved all this problem.

Excreta or faecal matter contains carbohydrates, protein and fats. In the first step, bacteria converts them into simple sugars, amino acids and fatty acids. In the next step, these break to form carbonic acid, alcohols, hydrogen and water. In the third step, acetic acid, hydrogen and carbon dioxide is formed and finally methane, carbon dioxide and water are formed. Methane can be used for cooking while water for irrigation. These series of stepss are called as- hydrolysis, acidogenesis, acetogenesis and methanogenesis.

These toilets don’t require any sewerage system and once bacteria are embedded in biodigesters, they can work for very long time without maintenance.

Hence statement 2 and 3 are correct.

You can see biodigester toilet below in image.

Q.3) Which of these technologies requires line of sight for communication?

Bluetooth
Wi-fi
Near field communication

Select the correct answer using the codes given below.
a) 1 and 2 only
b) 3 only
c) 1 and 3 only
d) None of the above

Ans- [D]

Explanation– Line of sight communication is a type of propagation of signals that can transmit and receive data only where transmit and receive stations are in view of each other without any sort of an obstacle between them.

NFC or near field communication, Wifi and Bluetooth don’t require such line of sight. FM radio, microwave and satellite transmission are examples of line-of-sight communication.

Q.4) Consider the following statements:

During the process of osmosis, the solvent travels from the concentrated solution to the dilute solution.
In the reverse osmosis, external pressure is applied to the dilute solution.

Which of the statements given above is/are correct?
a) 1 only
b) 2 only
c) Both 1 and 2
d) Neither 1 nor 2

Ans- [D]

Explanation- Statement 1 is wrong as in osmosis solvent molecules moves from low concentration solution to higher concentration solution through a semipermeable membrane.

Statement 2 is also wrong as in reverse osmosis external pressure is applied to the higher concentration solution. SOlvent in this case move from concentrated solution to dilute solution. External pressure applies is above the osmotic pressure.

Q.5) Hard water is not suitable for

Drinking
Washing cloth with soap
Use in boilers
Irrigating crops

Select the correct answer using the codes given below:
a) 1 and 3 only
b) 2 and 3 only
c) 1, 2 and 4 only
d) 1, 2, 3 and 4

Ans-[D]

Explanation- Hard water is that water which contains salts of calcium and magnesium principally as bicarbonates, chlorides, and sulfates. Ferrous iron may also be present in this water. This hardness is of two types, temporary and permanent.

Hardness that is caused by calcium bicarbonate is known as temporary, because boiling converts the bicarbonate to the insoluble carbonate; hardness from the other salts is called permanent.

This hard water is unfit for drinking as salt presents reacts with acids in stomach and cause digestive disorders.

These salts of hard water forms an insoluble gelatinous curd on reaction with soap and lather formation doesn’t occur and as such they are not fit for washing clothes even.

This water is unsuitable for boilers as calcium and magnesium in hard waters form a hard, adherent scale on the plates. As a result fuel consumption is increased, and the boiler deteriorates rapidly through increased external overheating.

Hard water is unsuitable for crops as salts present disturbs the normal chemistry of soil and clogs the irrigation channel pathways of plants.

Q.6) Which of the following pairs are matched Incorrectly?

Disease Cause

1) Minamata Disease Cadmiun Poisioning

2) Blue Baby Syndrom Nitrate Contamination

3) Itai Itai Disease Mercury Poisoning

Select the correct answer using the codes given below:
a) 1 only
b) 3 only
c) 1 and 3 only
d) 1, 2 and 3

Ans- [C] Explanation– Minamata diseases is caused by mercury poisoning. Blue baby syndrome is caused by nitrate contamination of groundwater and itai itai is cadmium poisoning disease. Only blue baby syndrome is correctly matched, hence ans is C.

Q.7) Rainbow is produced when sunlight falls on drops of rain. Which of the following physical phenomena are responsible for this?

Dispersion
Refraction
Internal reflection

Select the correct answer using the codes given below:
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

Answer: (d)

Explanation– The separation of visible light into its different colors is known as dispersion. As you can see in above figure, all three phenomenon happens when a rainbow is formed.

Q.8) Ionosphere facilitates radio communication because of

Presence of ozone causes the reflection of radio waves to Earth.
Radio waves have a very long wavelength.

Select the correct answer using the codes given below:
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Ans-[B]

Explanation- Statement 1 is wrong. Ionosphere contains charged particles due to which electromagnetic radio waves gets reflected and communication becomes possible. It is not due to ozone. Ozone is found mainly in Stratosphere and in traces in troposphere. It’s main function is absorption of UV rays. Statement 2 is right. You can see wavelength of Radio waves is in metres to kilometres.

Q.9) Various vitamin deficiency causes different diseases. In this regard which of the following pairs are correctly matched?

Niacin : Cheliosis
Thiamine : Pellagra
Retinol : Xerophthalmia

Select the correct answer using the codes given below.
a) 1 only
b) 2 only
c) 3 only
d) None

Ans- [C]

Explanation – Cheliosis is crack on outside of lips, a condition commonly caused by a deficiency of riboflavin, or vitamin B-2.

Pellagra is a vitamin deficiency disease caused by lack of niacin( vitamin B3 ). Thiamine is Vitamin B-1. Xerophthalmia is drying of tear glands caused due to deficiency of vitamin A ( retinol ) .

Q.10) Consider the following statements about antimicrobial resistance:

It is a natural phenomena.
Indiscriminate use of antibiotics leads to antimicrobial resistance.

Which of the statements given above is/are correct?
a) 1 only
b) 2 only
c) Both 1 and 2
d) Neither 1 nor 2

Ans- [B]

Explanation– Antibiotics resistance is not a natural phenomenon. This is due to large indiscriminate and unregulated use of antibiotics.

Q.1) Consider the following statements.
1. Ability of the lens to converge or diverge light rays depend upon its focal length.
2. A concave lens of very short focal length causes less divergence than a very long focal length concave lens.

Select the correct statement using the codes given below.
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Explanation- Statement 1 is obvious fact and correct.Statement 2 is wrong. A concave lens of very short focal length causes more divergence than a very long focal length concave lens by diverging light rays away from the optical centre.

Q.2) Arrange the following in decreasing order of refractive indexes.
1. Water
2. Air
3. Ice

Select the correct answer using the codes given below.
a) 3 >1 > 2
b) 1 > 3 >2
c) 3 > 2 > 1
d) 1 > 2 > 3

Explanation– Water refractive index is 1.33, of ice is 1.31 and air is 1.

Q.3) Convex mirrors are used commonly for rare view mirror. This is because:
1. It gives inverted and diminished image.
2. It has a wider field of view as they are curved inwards.

Select the correct answer using the codes given below.
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Explanation- Convex mirrors are commonly used as rear-view mirrors in vehicles. Convex mirrors are preferred because they always give an erect, though diminished, image. Also, they have a wider field of view as they are curved outwards. Thus, convex mirrors enable the driver to view much larger area than would be possible with a plane mirror.

Q.4) Which of the following are applications of Raman effect:
1. Monitoring of chemical purity in petro chemical industry
2. Identification of cancer
3. Study of gravity in black holes
4. Detection of Narcotics

Select the correct answer using the codes given below.
a) 2, 3 and 4 only
b) 1, 2 and 3 only
c) 1, 2 and 4 only
d) 1, 2, 3 and 4

Explanation- Raman effect is one of the few technique which can provide key information, easily and quickly, detailing the chemical composition and the structure of the investigated materials.Statement 3 is not the application of Raman effect. All other are common application of Raman effect.

Q.5) Consider the following statements about smart grid project.
1. It is the project of Union Ministry of water resources for solving water shortage.
2. Ranchi is selected as a first place to have smart grid system.

Select the incorrect statement using the codes given below.
a) 1 only
b) 2 only
c) Both 1 and 2
d) None of the above

Explanation– Smart grid is the project of New Delhi Municipal Council.

Q.6) Consider the following statements regarding the human eye.
1. Light enters the eye through a thin membrane known as pupil
2. Iris controls the size of the cornea
3. Eye lens always forms real and erect image on the retina.

Which of the above statements are true in the respect of anatomical structure of human eye?
a) 1 and 2 only
b) 1, 2 and 3
c) None of the above
d) 3 only

Explanation- Light enters the eye through a thin membrane known as Cornea. Iris controls the size of pupil. The eye lens always forms an inverted real image of the object on the retina. Hence all statements are wrong.

Q.7) Consider the following statements regarding eye donation:
1. Eye donors can belong to only some specific age bracket as per as WHO convention
2. People who use spectacles, or operated with cataract, who are diabetic, or have hypertension and who are asthma patients can not donate their eyes.
3. People infected with rabies and cholera can donate their eyes.

Select the correct statement using the codes given below.
a) 1 only
b) 2 and 3 only
c) 1, 2 and 3
d) None of the above

Explanation- Some basic facts about eye donation:

Eye donors can belong to any age group or sex. People who use spectacles, or those operated for cataract, can still donate the eyes.
People who are diabetic, have hypertension, asthma patients and those without communicable diseases can also donate eyes.
Eyes must be removed within 4-6 hours after death.
􀂄Eye removal takes only 10-15 minutes. It is a simple process and does not lead to any disfigurement.
Persons who were infected with or died because of AIDS, Hepatitis B or C, rabies, acute leukaemia, tetanus, cholera, meningitis or encephalitis cannot donate eyes.

Q.1) Consider the following pairs:

Vitamin Deficiency : Disease

Vitamin C : Scurvy
Vitamin D : Rickets
Vitamin E : Night blindness

Which of the pairs given above is/are correctly matched?
a) 1 and 2 only
b) 3 only
c) 1, 2 and 3
d) None

Ans-[A] Explanation – Nightblindness is caused by deficiency of vitamin A.
See the following link and learn the concepts very thoroughly.

Q.2) There is some concern regarding the nano-particles of some chemical elements that are used by the industry in the manufacture of various products. Why?

They can accumulate in the environment, and contaminate water and soil.
They can enter the food chains.
They can trigger the production of free radicals.

Select the correct answer using the code given below.
a) 1 and 2 only
b) 3 only
c) 1 and 3 only
d) 1, 2 and 3

Ans-[D] Explanation- All statements are correct.

A nanoparticle (or nanopowder or nanocluster or nanocrystal) is a microscopic particle with at least one dimension less than 100 nm. Nanoparticle research is currently an area of intense scientific research, due to a wide variety of potential applications in biomedical, optical, and electronic fields.

Nanoparticles can easily contaminate the environment. They may be directly toxic to microbes, plants, and animals. Silver nanoparticles, for instance (though they are not toxic to humans), dissolve in water and release silver ions which are antibacterial. If silver nanoparticles are released into the environment, these types of concentrated silver ion releases could devastate local bacterial populations, with drastic consequences for the affected ecosystems. In this way, it can also enter into the food chain if some bacteria like this infects the food. There are other ways too but nanoparticles can enter the food chains.

Free radicals are an uncharged molecule typically highly reactive and short-lived, having an unpaired valency electron. Nanoparticles are capable of making free radicals. For example, at nanoscale these particles can easily enter inside the cells and cause biochemical changes via formation of free radicals. In human cells also they enter like this. Free radicals in biochemical reaction of humans have been linked with the Alzheimer’s and Parkinson’s diseases.

Q.3) What is the difference between a CFL and an LED lamp?

To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi-conductor material.
The average life span of a CFL is much longer than that of an LED lamp.
A CFL is less energy-efficient as compared to an LED lamp.

Which of the statements given above is/are correct ?
a) 1 only.
b) 2 and 3 only.
c) 1 and 3 only.
d) 1, 2, and 3.

Ans- [C] Explanation– Statement 1 is correct .CFLs, like all fluorescent lamps, contain mercury as vapor inside the glass tubing. Most CFLs contain 3–5 mg per bulb, with the bulbs labeled “eco-friendly” containing as little as 1 mg.

Statement 2 is wrong as life of LED bulbs is upto 60-70 thousand hours and of CFL is 20-30 thousand hours

Statement 3 is correct. CFL are very much efficient than as compared to LED bulbs. This is one of the reason that government has started distributing LEDs in subsidised rates to phase out CFLs and bulbs.

Q.4) Which one of the following is the process involved in photosynthesis?
a) Potential energy is released to form free energy
b) Free energy is converted into potential energy and stored
c) Food is oxidized to release carbon dioxide and water
d) Oxygen is taken, and carbon dioxide and water vapour are given out

Ans-[B] Explanation – The energy that drives photosynthesis originates in the center of the sun, where mass is converted to heat by the fusion of hydrogen. Over time, the heat energy reaches the sun’s surface, where some of it is converted to light by black body radiation that reaches the earth. A small fraction of the visible light incident on the earth is absorbed by plants. Through a series of energy transducing reactions, photosynthetic organisms are able to transform light energy into chemical free energy in a stable form that can last for hundreds of millions of years (e.g., fossil fuels). Statement B is thus correct.

Q.5) Other than resistance to pests, what are the prospects for which genetically engineered plants have been created?

To enable them to withstand drought
To increase the nutritive value of the produce
To enable them to grow and do photosynthesis in spaceships and space stations
To increase their shelf life

Select the correct answer using the codes given below:
a) 1 and 2 Only
b) 3 and 4 Only
c) 1, 2 and 4 Only
d) 1, 2, 3 and 4

Ans-[C] Explanation- Genetically engineered plants involves insertion of some outside gene to insert some desirable property in the genome of the plant. This technique have been produced to do mainly statement 1,2 and 4. Statement 3 is wrong. There are experiments growing on to make plant grow in zero gravity. This is not the application yet of GMO. You can read about this growth of plant experiment here

Q.6) Recombinant DNA technology (Genetic Engineering) allows genes to be transferred

across different species of plants
from animals to plants
from microorganisms to higher organisms

Select the correct answer using the codes given below.
a) 1 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

Ans-[D] Explanation – Recombinant DNA (rDNA) technology involves laboratory methods of genetic recombination to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in the genome. Thus it allows genes to transfer genes across all these organisms.

Q.7 Which one of the following sets of elements was primarily responsible for the origin of life on the Earth?
a) Hydrogen, Oxygen, Sodium
b) Carbon, Hydrogen, Nitrogen
c) Oxygen, Calcium, Phosphorus
d) Carbon, Hydrogen, Potassium

Ans-[B] Explanation- Origin of the life depends upon 6 elements-carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus.

Q.8) Due to improper / indiscriminate disposal of old and used computers or their parts, which of the following are released into the environment as e-waste?

Beryllium
Cadmium
Chromium
Heptachlor
Mercury
Lead
Plutonium

Select the correct answer using the codes given below.
a) 1, 3, 4, 6 and 7 only
b) 1, 2, 3, 5 and 6 only
c) 2, 4, 5 and 7 only
d) 1, 2, 3, 4, 5, 6 and 7

Ans-[B] Explanation- Heptachlor is an organochlorine compound that was once used as an insecticide. Plutonium is a radioactive material used in the nuclear reactors and bombs. Leaving these two all other are commonly used elements in the electronic circuits of computers.

Q.9) Consider the following phenomena:

Size of the sun at dusk
Colour of the sun at dawn
Moon being visible at dawn
Twinkle of stars in the sky
Polestar being visible in the sky

Which of the above are optical illusions?
a) 1, 2 and 3
b) 3, 4 and 5
c) 1, 2 and 4
d) 2, 3 and 5

Ans-[C] Explanation– An optical illusion also called a visual illusion is characterized by visually perceived images that differ from object than reality. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source. Moon being visible in dawn and polestar being visible in sky are not any illusion. Size of the sun which appears big, color of the sun at dawn and twinkle of stars in the sky are not actual phenomenon but happens due to various factors such as refraction, different density of the air layers etc.

Q.1) Surface of the copper vessels and utensils turns black with time. It is the result of
a) Reaction of copper with the Nitrogen
b) Reaction of moisture with the copper
c) Oxidation of the copper to copper oxide
d) Due to presence of carbon dioxide in the air

Ans-[C] Explanation-This is due to the formation of copper oxide in the presence of oxygen in the air. Copper is said to be oxidized in this way.

Q.2) Consider the following statements:
1. Gain of electrons by atoms, molecules or ions is also known as Reduction.
2. Gain of Hydrogen by molecules or chemical substances is also known as Reduction.

Which of the above statements is/are correct?
a)1 Only
b)2 Only
c)Both 1 and 2
d)Neither 1 nor 2

Ans-[C]

Explanation– This is the definition of Reduction.
Reduction is gain of electrons, gain of hydrogen or loss of oxygen whereas oxidation is loss of hydrogen, loss of electrons or gain of oxygen.

Q.3) Consider the following statements:
1.Hydrogen gas is flammable and combustible gas.
2.Oxygen is non flammable, combustible gas.

Select the correct statement using the codes given below.
a)1 Only
b)2 Only
c)Both 1 and 2
d)Neither 1 nor 2

Ans-[A] Explanation– Oxygen is the non flammable and non combustible gas. Oxygen only helps in combustion.
Hydrogen gas is a flammable combustible gas, it burns with a pop sound.

Q.4) Consider the following statements:
1.Nettle is a herbaceous plant whose leaves secrete Methanoic acid.
2.Formic acid is found in the stings of ants and bees.

Select the correct statement using the codes given below.
a)1 Only
b)2 Only
c)Both 1 and 2
d)Neither 1 nor 2

Ans-[C] Explanation– Nettle is a planet whose leaves secrete Methanoic acids which when touched gives a stinging effect. This acid is also found in the stings of bees and ants. Formic acid is another name of Methanoic acid.

Q.5) Which of the following are uses of Bleaching powder?
1. Used in the textile industry
2. as an oxidising agent
3. for disinfecting drinking water.

Select the correct answer using the codes given below.
a) 1 and 3 only
b) 3 only
c) 2 and 3 only
d) 1, 2 and 3

Ans-[D] Explanation– Bleaching powder is used in:
1. for bleaching cotton and linen in the textile industry, for bleaching wood pulp in paper factories and for bleaching washed clothes in laundry;
2. as an oxidising agent in many chemical industries; and
3. for disinfecting drinking water to make it free of germs.

Q.6) Consider the following statements:
1. Gravity does not have role in the deciding direction that plant grows in.
2. Growth of pollen tubes towards ovules is result of geotropism.

Select the incorrect statement using the codes given below.
a)1 Only
b)2 Only
c)Both 1 and 2
d)Neither 1 nor 2

Ans-[C] Explanation-Environmental triggers such as light, or gravity change the directions that plant parts grow in. These directional, or tropic, movements can be either towards the stimulus, or away from it. So, in two different kinds of phototropic movement which is movement influenced by light, shoots respond by bending towards light while roots respond by bending away from it.

The roots of a plant always grow downwards while the shoots usually grow upwards and away from the earth. This upward and downward growth of shoots and roots, respectively, in response to the pull of earth or gravity is, geotropism. Thus gravity has a role in the direction that plant grows in.

Growth of pollen tubes towards ovules is due to chemotropism.

Q.7) Fly Ash is used in
1. Mine reclamation
2. Concrete production
3. Cosmetics
4. Toothpaste
5. Stabalisation of soft soil
6. Application on rivers to melt ice

Select the correct answer using the codes given below.
a) 1, 2, 3 and 5
b) 3, 4, 5 and 6
c) 1, 2, 3, 5 and 6
d) 1, 2, 3, 4, 5 and 6

Ans-[D] Explanation– Fly ash is used in the cement industry, brick manufacturing, construction of road embankment, saline and soil waste management,agriculture, cosmetics, toothpaste, horticulture, forestry and mine filling.

Q.8) As per latest theory on cosmos, Consider the following.
1.Dark energy
2.Dark matter
3.Matter which we can see

Arrange them in decreasing order as fraction of universe is:
a)1 > 2 > 3
b)2 > 1 > 3
c) 2 > 3 > 1
d) 3 > 2 > 1

Ans-[A]

Explanation-Dark matter is invisible matter which is holding the galaxies together. In the accelerating and expanding universe, Dark energy is an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe. 70% of the universe is dark energy, 25% dark matter and 5% is just what we can see.

Q.9)Consider the following statements:
1.Protons are fundamental particles
2.Gravitational forces does not apply to elementary particles.

Select the incorrect statement using the codes given below.
a) 1 Only
b) 2 Only
c) Both 1 and 2
d) Neither 1 nor 2

Ans[C] Explanation- Protons are not fundamental particles. Fundamental particles are those which are smallest particles and which make the protons and neutrons. These fundamental particles can not be broken down into other smaller particles. Quarks and electrons are fundamental particles.

Gravitational forces applies to all particles. But as their mass is very small, this force is very very small and negligible.

Q.1) Italian varieties of Honey bee are used for commercial production of Honey. This is due to1. They have high collection capacity2. They sting less3. They stay in beehive longer periods.

Select the correct answer using the codes given below.
a) 2 onlyb) 1 and 2 onlyc) 2 and 3 onlyd) 1, 2 and 3

Ans – [D] Explanation – It is taken verbatim from class 9 NCERT page 213. All three are reasons of it.

Q.2) Consider the following statements.1. In organic farming there is no or minimal use of fertilizers while other things such as pesticides and insecticides are commonly used.2. Blue green algae is used in preparation of Bio-fertilizers.

Select the correct answer using the codes given below.
a) 1 onlyb) 2 onlyc) Both 1 and 2d) Neither 1 nor 2

Ans – [B] Explanation – Organic farming is a farming system with minimal or no use of chemicals as fertilizers, herbicides, pesticides etc. and with a maximum input of organic manures, recycled farm-wastes (straw and livestock excreta), use of bio-agents such as culture of blue green algae in preparation of bio-fertilizers, neem leaves or turmeric specifically in grain storage as bio-pesticides, with healthy cropping systems.

Q.3) It is harder to make anti viral medicines than antibiotics due toa) Viruses are very complex organisms to understandb) Viruses have very effective resistance mechanismc) Viruses have few biochemical reactions of their ownd) All of the above

Ans-[C] Explanation-is harder than making antibacterial medicines is that viruses have few biochemical mechanisms of their own. They enter our cells and use our machinery for their life processes. This means that there are relatively few virus-specific targets to aim at.

Q.4) The nitrogenous base Purine occurring in RNA isa) Cytosineb) Uracilc) Guanined) Thymine

Ans-[C] Explanation-There are total 5 Nitrogenous bases occurring in DNA and RNA. Two are purines and three are Pyrimidines. Purines are Adenine and Guanine and Pyrimidines are Cytosine, Uracil and Thymine. In DNA we have, Adenine, Thymine, Guanine and Cytosine. In RNA, we have Adenine Uracil Guanine and Cytosine.

Q.5) Which pair of diseases are caused by Virus?a) Tetanus and Typhoidb) Syphilis and AIDSc) Measles and rabiesd) Sleeping sickness and whooping cough

Ans-[C] Explanation- The rabies virus is a neurotropic virus that causes rabies in humans and animals.Rabies transmission can occur through the saliva of animals and less commonly through contact with human saliva. Measles virus (MeV) is a single-stranded, negative-sense, enveloped (non-segmented) RNA virus of the genus Morbillivirus within the family Paramyxoviridae.

Whooping cough (pertussis) is an infection of the respiratory system caused by the bacterium Bordetella pertussis.

African trypanosomiasis or sleeping sickness is a parasitic disease of humans and other animals. It is caused by protozoa of the species Trypanosoma brucei.

Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum subspecies pallidum.

Human immunodeficiency virus (HIV) is the virus that causes AIDS.

The causative agent of tetanus disease is Clostridium tetani, an anaerobic spore-forming bacterium, whose natural habitat is soil, dust, and intestinal tracts of various animals.

Typhoid fever is an acute illness associated with fever caused by the Salmonella typhi bacteria.

Q.6) Hypersensitivity is related to
a) Aberrant functioning of the immune systemb) Increase in ambient temperaturec) Age of individuald) Food habits

Ans – [A] Explanation – Hypersensitivity (also called hypersensitivity reaction or intolerance) is a set of undesirable reactions produced by the normal immune system, including allergies and autoimmunity. These reactions may be damaging, uncomfortable, or occasionally fatal.

Q.7) Influenza virus hasa) DNA
b) RNA
c) DNA and RNAd) Only proteins and no nucleic acid

Ans-[B] Explanation-An RNA virus is a virus that has RNA (ribonucleic acid) as its genetic material.This nucleic acid is usually single-stranded RNA but may be double-stranded RNA. Notable human diseases caused by RNA viruses include Ebola hemorrhoragic fever, SARS, influenza,hepatitis C, West Nile fever, polio, and measles.

Q.8) Energy needed to Ionize an atom is greatest fora) Alkali metalsb) Rare earth metalsc) Noble gasesd) Transition elements

Ans-[C] Explanation-Noble gases are very stable as their electronic configuration is complete and that’s why it will require lot of energy to ionize an atom.

Q.9) Photodynamic theory is related with thea) Polaroid photographyb) Cancer treatmentc) Measurement of high speedd) Growth of plants

Ans-[B] Explanation-You can read about it in detail here

Q.1) Rusting of an article made up of iron is called-
a) corrosion and it is a physical as well as chemical change
b) dissolution and it is a physical change
c) corrosion and it is a chemical change
d) dissolution and it is a chemical change

Ans – [C] Explanation – Rusting of an iron is a corrosion and it is a chemical change. It is an iron oxide, usually red oxide formed by the redox reaction of iron and oxygen in the presence of water or air moisture.

Q.2) What is vital capacity of our lungs?a) Total lungs capacity minus residual volumeb) Inspiratory reserve volume plus tidal volumec) Total lungs capacity minus expiratory reserve volumed) Inspiratory reserve volume plus expiratory reserve volume

Ans [A] Explanation– Vital capacity(VC) is the maximum amount of air a person can expel from the lungs after a maximum inhalation. It is equal to the sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume.

Tidal volume(TV) is the lung volume representing the normal volume of air displaced between normal inhalation and exhalation when extra effort is not applied. In a healthy, young human adult, tidal volume is approximately 500 mL per inspiration.

The inspiratory reserve volume (IRV), about 3,100 mL, is the additional air that can be forcibly inhaled after the inspiration of a normal tidal volume. The expiratory reserve volume (ERV), about 1,200 mL, is the additional air that can be forcibly exhaled after the expiration of a normal tidal volume.

Residual volume (RV), about 1,200 mL, is the volume of air still remaining in the lungs after the expiratory reserve volume is exhaled

Vital capacity = TV + IRV + ERV
Total lung capacity = VC + Residual volumeSo we can say that VC = Total lung capacity – Residual volume.

Q.3) All eukaryotic unicellular organisms belong toa) Monerab) Protistac) Fungid) Bacteria

Ans-[B] Explanation-Protista is a group of all unicellular eukaryotic animals and plants. Monera includes prokaryotic cells.

Q.4)Which one of the following is not a disorder of bone?
a) Arthritis
b) Osteoporosis
c) Rickets
d)Atherosclerosis

Ans-[D] Explanation- Atherosclerosis, or hardening of the arteries, is a condition in which plaque builds up inside the arteries. Plaque is made of cholesterol, fatty substances, cellular waste products, calcium and fibrin (a clotting material in the blood).

Q.5) Select the right match of endocrine gland and their hormones among the options given below:1. Pineal i. Epinephrine2. Thyroid ii. Melatonin3. Ovary iii. Estrogen4. Adrenal medulla iv. Tetraiodothyronine

Select the correct answer using the codes given below.
a) A-iv, B-ii, C-iii, D-ib) A-ii, B-iv, C-i, D-iiic) A-iv, B-ii, C-i, D-iiid) A-ii, B-iv, C-iii, D-i

Ans-[D] Explanation- The pineal gland is a small pinecone-shaped mass of glandular tissue found just posterior to the thalamus of the brain. The pineal gland produces the hormone melatonin that helps to regulate the human sleep-wake cycle known as the circadian rhythm.

The 2 main thyroid hormones are T3 (triiodothyronine) and T4 (thyroxine or tetraiodothyronine). T3 and T4 regulate your body’s temperature, metabolism and heart rate. The amount of thyroid hormones secreted is controlled by another hormone, called thyroid stimulating hormone (TSH), which is released from the pituitary gland in your brain.

Ovary gland main hormones are—estrogen and progesterone.

Medulla cells secretes catecholamines epinephrine, norepinephrine, and dopamine.

Q.6) Consider the following statements about Bedaquiline.
1. It has been recommended against all kind of Bacterial infections.
2. It has been put in the WHO list of essential medicines.

Which of the above statements is/are correct?
a)1 only
b)2 only
c)Both 1 and 2
d)Neither 1 nor 2

Ans-[B] Explanation-Bedaquiline has been released specifically to treat TB patients with bacteria that are resistant to rifampicin as well as to isoniazid, another core anti-TB drug, and thus suffer from multidrug-resistant tuberculosis. Statement 1 is thus wrong. Statement 2 is right. It has been put in the list of most essential medicines. Read here

Q.7) A gland not associated with the alimentary canal is
a) Pancreasb) Adrenalc) Liverd) Salivary glands

Ans-[B] Explanation- The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which produces steroid hormones and an inner medulla.

Q.8) Consider the following statements with respect to ARIES observatory.1. It has been provided India’s largest telescope recently which will provide more clearer pictures than Hubbles’ telescope.2. It is made in collaboration with China.

Which of the above statements is/are correct?a) 1 onlyb) 2 onlyc) Both 1 and 2d) Neither 1 nor 2

Ans – [A] Explanation – Statement 2 is wrong. It is made in collaboration with the Belgium. Observatory ARIES, an autonomous research body under the Department of Science and Technology, has been given India’s largest ground-based optical telescope. It was put into operation jointly by PM of two countries. Its defining feature will be a 3.6-metre-wide primary mirror, which will collect light from its field of view and focus it onto a 0.9-m secondary mirror, which in turn will divert it into various detectors for analysis. This arrangement, called the Ritchey-Chrétien design. Although, it does capture cosmic panoramas but clarity is not better than Hubble as hubble is located in the space and Earth’s atmosphere can not interfere much as in this case.

Q.9) Which of the following statements is correct?
a) conversion of solid into vapours without passing through the liquid state is called vapourisation.b) conversion of solid into vapors without passing through the liquid state is called sublimation.c) conversion of vapours into solid without passing through the liquid state is called freezing.d) conversion of solid into liquid is called sublimation.

Ans-[B] Explanation- This is the standard definition of sublimation.

Q.1) Consider the following statements about Plasmonics.1. Plasmonics is the study of electrons of Plasma matter present in the stars like sun.2. Plasmonics techniques will soon be used in the Bio-sensors technology.

Which of the above statement(s) is/are correct?a) 1 onlyb) 2 onlyc) Both 1 and 2d) Neither 1 nor 2

Ans-[B] Explanation – Plasmonics is the study of the interaction between electromagnetic field and free electrons present in a metal and it is not study of plasma matter present in the sun. Hence,statement 1 is wrong.

As we know, Free electrons in the metal can be excited by the electric component of light to have collective oscillations. Plasmonics make use of this property only and is the developing field of nano-photonics that holds the promise of molecular-size optical device technology. Its various applications are use in the bio-sensors, surface enhanced Raman spectroscopy, Laser antennas and fibres, Trapping and manipulation of Nanoparticles, controlled drug delivery, cancer therapy and contrast imaging.

Q.2) 3D movies are very famous these days. Consider the following statement(s) related with 3D movies:1. Modern 3D movies make use of red and blue light instead of Polarized light.2. 3D glasses make use of polarized filters to enable audience to watch 3D movie.

Which of the above statement(s) is/are incorrect?a) 1 onlyb) 2 onlyc) Both 1 and 2d) Neither 1 nor 2

Ans – [A]

Explanation– This link nicely explains how 3D movies work.

Q.3) What does dosimeter measures?a) It measures level of noises in environmentb) It measures exposure to non-ionizing radiationc) It measures dosage of medicines in the blood in real timed) It measures exposure to ionizing radiation.

Ans – [D]

Explanation – A radiation dosimeter is a device that measures exposure to ionizing radiation. It has two main uses: for human radiation protection and for measurement of radiation dose in both medical and industrial processes.

Q.4) What are the after effects of nuclear winter?1. No oxygen regenration2. Change in the radiation balance of the earth3. Change in the heat budget of the earth4. Disappearance of Monsoon and seasonal rains

Select the correct answer using the codes given below.
a) 1 and 2 onlyb) 1, 2 and 3 onlyc) 2 ,3 and 4 onlyd) 1, 2, 3 and 4

Ans – [D]

Explanation –

Nuclear winter can be seen in places where nuclear bomb is dropped or exploded. Due to the explosion, suspended particles like radioactive debris shoot and spread upto stratosphere and form a covering causing almost complete stopping of the sunlight to reach the earth surface. As a result, photosynthesis process stops and no oxygen is produced after sometime. If large scale fire happens, than a big portion of the oxygen is used up in the combustion and other process like respiration, industrial processes etc causes further decreases in percentage of oxygen in atmosphere. Level of carbon dioxide keeps on increasing as Plants can utilize it. This in turn change the radiation and heat budget of the earth. This change in the budget causes catastrophic changes in the wind circulation and thus, seasonal winds and monsoon may starts weakening and disappearing.

Q.5) Consider the following statements related with ‘Fire Ice’.1. Fire ice are mainly Methane hydrates2. Fire ice deposits are found at higher pressure than conventional gas deposits.3. Its extraction is cheaper than conventional gas deposits.

Which of the above statement(s) is/are correct?a) 1 onlyb) 2 and 3 onlyc) 1 and 2 onlyd) None of them

Ans – [A]

Explanation – Methane clathrate also called methane hydrate, hydro-methane, methane ice, fire ice, natural gas hydrate, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice.

Their Deposits are found at lower pressure than conventional gas deposits, meaning it will require more energy (and money) to pump the gas to where it needs to be transported.

Q.6) Which of the following statement is not true about Astrosat?a) It is used for observation of the objects of the universe and telecommunication also.b) It observes universe only through the high energy X ray regions of the electromagnetic spectrum.c) It is India’s first dedicated single wavelength space observatoryd) All of the above

Ans – [D]

Explanation- ASTROSAT is India’s first dedicated multi wavelength space observatory. This scientific satellite mission endeavours for a more detailed understanding of our universe. One of the unique features of ASTROSAT mission is that it enables the simultaneous multi-wavelength observations of various astronomical objects with a single satellite. ASTROSAT will observe universe in the optical, Ultraviolet, low and high energy X-ray regions of the electromagnetic spectrum, whereas most other scientific satellites are capable of observing a narrow range of wavelength band.

The scientific objectives of ASTROSAT mission are:

To understand high energy processes in binary star systems containing neutron stars and black holes
Estimate magnetic fields of neutron stars
Study star birth regions and high energy processes in star systems lying beyond our galaxy
Detect new briefly bright X-ray sources in the sky
Perform a limited deep field survey of the Universe in the Ultraviolet region

Q.7) Consider the following statements about solar water heater.1. It works on the principle of Greenhouse effect2. Pipes are painted with white colors3. Copper pipes are used in the solar water heater

Select the correct statement using the codes given below.
a) 1 and 2 onlyb) 2 and 3 onlyc) 1 and 3 onlyd) 1,2 and 3

Ans – [C]

Explanation – Statement 2 is wrong. Pipes are painted black and not white to enable maximum absorption of sunlight. You can read about working of solar heater here andhere.

Q.8) Which among the following has least wavelength?a) Blue lightb) Green lightc) Red lightd) Yellow light

Ans – [A]

Explanation – VIBGYOR is the arrangement of light rays in the increasing order of wavelength and decreasing order of energy. Blue light has the least wavelength among all these.

Q.1) Energy(ies)/Processes that influence the ocean currents are1. Solar energy2. Wind energy3. Gravitational energy4. Earth rotation

Select the correct answer using the codes given below.
a) 1, 2 and 3 onlyb) 1, 2 and 4 onlyc) 1, 2, 3 and 4d) 1 and 2 only

Ans – [C]

Explanation – Ocean currents can be generated by wind, density differences in water masses caused by temperature and salinity variations, coriolis force, gravity, and events such as earthquakes.

Q.2) RADAR gun is used fora) Airport scannersb) Burning the trashc) Measurement of speed of vehicles by Policed) Used in the missiles

Ans – [C]

Explanation – A radar speed gun is a device used to measure the speed of moving objects. It is used in law-enforcement to measure the speed of moving vehicles.

Q.3) Consider the following statements about Nirbhaya Missile.1. It is a subsonic missile2. It is a surface to air missile3. It can not carry Nuclear weapons

Select the correct statement using the codes given below.
a) 1 onlyb) 1, 2 and 3c) 2 and 3 onlyd) None of the above

Ans – [A]

Explanation – Nirbhay is a long range, surface to surface subsonic cruise missile designed and developed in India by the Defence Research and Development Organisation. It is an all-weather, low-cost, long-range cruise missile capable of carrying conventional and nuclear war heads. The missile has a range of more than 1000 km.

Q.4) Connect to decode is related witha) Zika Virusb) AIDS virusc) Malariad) Tuberculosis

Ans – [D]

Explanation – Connect to decode is a quest towards conquest of Tuberculosis, a massive initiative to further the understanding of the biology of the causative organism, Mycobacterium tuberculosis. The objective is to accelerate the discovery of novel drugs for TB, a disease neglected by Pharmaceutical enterprises.

Q.5) SCRAM term is related witha) emergency shutdown of nuclear reactorb) It is a term related with the computer memoryc) Transmission mode in which device can send and receive signals simultaneouslyd) Control device of a cruise missile

Ans – [A]

Explanation – A scram or SCRAM is an emergency shutdown of a nuclear reactor, though the term has been extended to cover shutdowns of other complex operations, such as server farms. In commercial reactor operations, this type of shutdown is often referred to as a “SCRAM” at boiling water reactors (BWR), and as a “reactor trip” at pressurized water reactors. In many cases, a SCRAM is part of the routine shutdown procedure as well.

Q.6) Consider the following statements about Project Loon.1. It is a Google Project.2. Balloons will fly on the tropopause layer of the atmosphere

Which of the above statements is/are correct?a) 1 onlyb) 2 onlyc) Both 1 and 2d) Neither 1 nor 2

Ans – [A]

Explanation – Project Loon is a research and development project being developed by “X” (formerly Google X) with the mission of providing Internet access to rural and remote areas. The project uses high-altitude balloons placed in the stratosphere at an altitude of about 18 km (11 mi) to create an aerial wireless network with up to 4G-LTE speeds. It was named Project Loon, since Google itself found the very idea of providing internet access to the remaining 5 billion population unprecedented and crazy.

Q.7) Consider the following statements.1. Use of UAV2. Crop Insurance

Which of the above is/are associated with KISAN Project?a) 1 onlyb) 2 onlyc) Both 1 and 2d) Neither 1 nor 2

Ans – [C]

Explanation – Government recently launched project KISAN – that will use space technology and drone-based imaging for estimating crop yield in better way and also launched an Android App, designed by the country’s space agency ISRO, to assess real time data on hailstorm occurrences to figure out crop loss in affected areas.

Both these technical support systems will help the government in effectively running the crop insurance schemes and disbursing compensation to farmers.

Q1. For which of the following is capillarity not the only reason?

a) Blotting of ink

b) Rising of underground water

c)Spread of water drop on a cotton cloth

d)Rising of water from the roots of a plant to its foliage

Ans -[B]. This question was asked in UPSC,1999. The catch is that the question is asking “not the only reason”. Hence, option B is the most suitable one as rise of underground water happens due to many other reasons as well e.g. recharge due to high rainfall, recharge due to irrigation etc.

Q2. LISA project is associated with

a) Study of ocean currents

b) AIDS test

c) Study of gravitational waves

d) Study of earthquake waves.

Ans – [C]. LISA, the Laser Interferometer Space Antenna project is a project to study the gravitational waves.

Q3. Bedaquiline is a drug used to treat

a) Cancer

b) Tuberculosis

c) Japenese Enciphalatis

d) None of these

Ans- [B]. Bedaquiline is a drug for the treatment of drug resistant TB. In India the drug will be introduced in 104 districts across 5 states.

Q4. Consider the following statements about a thermos flask:

1. It is a practical device in which the heat flowing into or out of the system by conduction,convection or radiation is used as much as possible

2. It consists of a double walled glass vessel

3. The heat transfer by convection is minimised by silvering the surfaces and the radiation is minimised by evacuating the space between the walls

Which if the statements given above is/are true?

a) 1 and 2 only

b) 2 and 3 only

c) 1 and 3 only

d) 1, 2 and 3

Ans -[A]. Statement 3 is wrong. The heat transfer by radiation is minimised by silvering the surfaces and ctransfer of heat by onduction is minimised by evacuation space between the walls.

Q5. Consider the following statements regarding Reusable Launch Vehicle (RLV):

1. It is a vehicle which on taking the satellite into the space, comes back to the earth and can be used for future launches

2. India is the first country to test Reusable Launch Vehicle

3. One of the advantages of RLV is that it will not add up to the space debris

Which of the statements given above is/are true?

a) 1 and 2 only

b) 2 and 3 only

c) 1 and 3 only

d) 1, 2 and 3

Ans – [C]. India is not the first country to test RLV. US, Japan, France and Russia have also tested it. Rest all the statements are true.

Q6. A person stands at the middle point of a wooden ladder which starts slipping between a vertical wall and the floor of a room, while continuing to remain in a vertical plane. The path traced by a person standing at the middle point of the slipping ladder is :

a) a straight line

b) a elliptical path

c)a circular path

d) a parabolic path

Ans- [C].

Mercury and its compounds are toxic; despite it is used in variety of products. It is used in

(1) Medicines

(2) Paints

(3) Eye-Drops

(4) Antiseptics

(5) Fungicides

Select the correct codes

(a) 1 and 2

(b) 1,2,3

(d) 1,2,3,4 and 5

Answer: D

Q-‘Ethanol’ has widespread usages and application. Consider the statements with reference to it

(1) It cannot be used as rocket propellant

(2) It can be used in thermometer

(3) It can be used as an antiseptic

(4) It causes cancer

(5) It can cause birth defects

(6) It cannot be used in DNA extraction because it is highly toxic

Correct code/s

(a) 1 ,2 ,3 and 5

(b) 1 ,2, 4 ,5 and 6

(d) 2,3,4 and 5

Answer: (d)

Which of the following is/are the example/examples of chemical change? (2014)

(1) Crystallization of sodium chloride

(2) Melting of ice

(3) Souring of milk

Select the correct answer using the code given below.

(a) 1 and 2 only

(b) 3 only

(d) None

Answer: b

Q- The surface of a lake is frozen in severe winter, but the water at its bottom is still liquid. What is the reason? (2011)

(a) Ice is a bad conductor of heat

(b) Since the surface of the lake is at the same temperature as the air, no heat is lost

(c) The density of water is maximum at 4°C

(d) None of the statements (a), (b) and (c) given above is correct

Solution: C

Q-The function of heavy water in a nuclear reactor is to (2011)

(a) Slow down the speed of neutrons

(b) Increase the speed of neutrons

(c) Cool down the reactor

(d) Stop the nuclear reaction

Solution. A

Q- During a thunderstorm, the thunder in the skies is produced by the (2013)

1. Meeting of cumulonimbus clouds in the sky

2. Lightning that separates the nimbus clouds

3. Violent upward movement of air and water particles

Select the correct answer using the codes given below.

(a) 1 only

(b) 2 and 3

(d) None of the above produces the thunder

Solution: C

Q- Consider the following phenomena: (2013)

1. Size of the sun at dusk

2. Colour of the sun at dawn

3. Moon being visible at dawn

4. Twinkle of stars in the sky

5. Polestar being visible in the sky

Which of the above are optical illusions?

(a) 1, 2 and 3

(b) 3, 4 and 5

(d) 2, 3 and 5

Solution: C

1. Which among the following is the edible part in Rice?

[A]Fruit

[B]Cotyledons

[C]Endosperm

[D]Embryo

Answer- Endosperm It’s a very common question but can confuse many of you. Most of the essential micronutrients are almost exclusively stored in the husk, aleurone and embryo of rice, which are removed during the polishing process. Polishing of rice is required as the oil-rich aleurone layer turns the seed rancid upon storage and therefore making rice unsuitable for consumption. Consequently, the rice endosperm that comprises the edible part of rice for humans lacks or contains only small amount of key micronutrients (e.g., iron, zinc, protein, provitamin A, and other vitamins) that are essential for a healthy diet. Considering the facts above and severity of widespread micronutrient malnutrition, iron biofortification in rice endosperm is a promising strategy to overcome iron deficiency effectively.

2. In context with computers, what can be the uses of cookies?

1. Maintain Information

2. Run a programme

3. Deliver a Virus

Choose the correct option:

[A]Only 1

[B]1 & 2

[C]2 & 3

[D]1, 2 & 3

Answer:Only 1 A cookie is a text string that is included with Hypertext Transfer Protocol requests and responses. Cookies are used to maintain information as you navigate different pages on a website or return to the website at a later time. Cookies cannot be used to run code (programmes) or deliver viruses to your computer. One of their primary purposes is to provide a convenience feature that you can use to save time — it tells the web server that you have returned to the page. If you personalize web pages or register for products and services, a cookie helps the page server recall your specific information, like billing address, shipping address.

3. How does calcium carbide ripen mangoes?

[A]It reacts with moisture and releases Ethylene

[B]It reacts with moisture and releases Ethyne

[C]It reacts with moisture and releases Acetaldehyde, which in turn releases ethylene

[D]It reacts with starch and releases Acetylene

Answer- It reacts with moisture and releases Ethyne For reasons of safe transportation of fruits, mangoes, bananas etc are picked before they ripen fully. Slightly green harvested mangoes are subjected to small containers of calcium carbide (CaC2) with a plastic covering. CaC2 reacts with the moisture in the air to release acetylene (or ethyne) gas as follows: CaC2 + 2 H2O → C2H2 + Ca(OH)2 This option may give you slightest confusion if you don’t know the difference between Ethylene and Ethyne (Acetylene). Both are chemical substances produced by fruits to accelerate the normal process of fruit maturation — is a ripening hormone. Ethylene is C2H4 and has a carbon-carbon double bond. Acetylene is C2H2 and has a carbon-carbon triple bind. Acetylene contains more energy and burns hotter than ethylene. Ethylene is a gaseous compound , Acetylene is the chemical compound , which is the simplest alkyne and is also a hydrocarbon while Ethylene is the simplest alkene and classified as an unsaturated hydrocarbon. I hope you will never forget it now

7. Why do the bacteria develop resistance after slowly being exposed to a particular antibiotic?

1. Due to mutation in genes

2. Due to Horizontal Gene Transfer

3. Due to Vertical Gene Transfer

Choose the correct option: [A]Only 1 [B]Only 1 & 2 [C]Only 2 & 3 [D]1, 2 & 3

Answer -Only 1 & 2

This is very carefully framed question and would clear the concept of antibiotic resistance, Horizontal Gene Transfer and Vertical Gene Transfer. Antibiotic resistance occurs from random mutations, the first choice given is correct. The slow exposure to an antibiotic will give more chance for mutations to occur. Most antibiotics are derived from naturally derived from organisms, penicillin was derived from the mould Penicillium, other antibiotics have also been extracted from bacteria, and these bacteria will be resistant to that antibiotic. The Horizontal Gene Transfer is considered to be the main culprit of the antibiotic resistance. Horizontal gene transfer (HGT), also lateral gene transfer (LGT), is any process in which an organism incorporates genetic material from another organism without being the offspring of that organism. By contrast, vertical transfer occurs when an organism receives genetic material from its ancestor, e.g., its parent or a species from which it has evolved. Horizontal gene transfer is also the primary reason for bacterial antibiotic resistance and this often involves plasmids. Genes that are responsible for antibiotic resistance in one species of bacteria can be transferred to another species of bacteria through various mechanisms. The resistance spreads across bacterial species usually by transfer of genetic material via a vector, this vector tends to be a circular piece of genetic material known as a plasmid. Operons within the plasmid code for several genes, a combination of proteins including an enzyme which is able to deactivate antibiotics, for example beta-lactamase is an enzyme which cleaves beta-lactam rings, deactivating penicillin and its derivatives (although certain derivatives like methicillin are resistant to beta lactamases). Sequences within plasmids that can transfer to the cell’s own genetic material is known as a transposon. The third choice “vertical gene transfer’ is not correct. Vertical Gene Transfer means reproduction.

CIVIL SERVICE EXAM PREPARATION NOTES

Wikipedia

Friday, 17 June 2016

SCIENCE AND TECH CONCEPTS

SCIENCE AND TECH CONCEPTS

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