ibps afo mains previous year paper 2012

ibps afo mains previous year question paper 2012 with answer and detail explanation of each option very important for upcoming IBPS AFO exam and NABARD exam

IBPS AFO mains previous year question paper

1. A phenomenon wherein a single gene has more than one phenotypic effect is known as

(1) Pleiotropism
(2) Epistasis
(3) Hypostasis
(4) Duplicate genes
(5) None of these

ans:- (1) Pleiotropism

Pleiotropism, or pleiotropy, is the phenomenon where a single gene influences multiple phenotypic traits. This occurs because a single gene can produce a protein that functions in different ways in various tissues or at different times in development. For example, a gene might encode an enzyme that participates in several metabolic pathways, affecting different traits.

In contrast:

Epistasis (option 2) involves the interaction of different genes, where one gene masks or modifies the effect of another gene.
Hypostasis (option 3) refers to the gene whose effect is masked by another gene in epistatic interactions.
Duplicate genes (option 4) are genes that have similar sequences and functions, often arising from gene duplication events, but do not explain a single gene affecting multiple traits.

2. Which one of the following is a rich source of protein?

(1) Scytonema
(2) Spirulina
(3) Spirogyra
(4) Stigonema
(5) None of these

ans:- (2) Spirulina

Explanation:
Spirulina is a type of blue-green algae that is widely recognized as a rich source of protein. It is commonly used as a dietary supplement because it contains a high percentage of protein (about 60-70% of its dry weight) along with essential amino acids, vitamins, and minerals. This makes it a popular choice for people looking to increase their protein intake, especially in vegetarian and vegan diets.

Scytonema, Spirogyra, and Stigonema are other types of algae, but they are not particularly known for their high protein content compared to Spirulina.

Spirulina (option 2): Spirulina is a type of blue-green algae that is renowned for its high protein content. It typically consists of 60-70% protein by dry weight, making it an excellent source of protein. Additionally, Spirulina is rich in essential amino acids, vitamins (such as B-complex vitamins), minerals (including iron and calcium), and antioxidants. It is commonly used as a dietary supplement and is particularly popular among vegetarians and vegans for its nutritional benefits.

Scytonema (option 1): Scytonema is a genus of cyanobacteria (blue-green algae) found in various aquatic environments. While it may contain some protein, it is not particularly noted for being a rich source of protein compared to Spirulina. Its primary significance lies in its role in nitrogen fixation and its presence in different ecological niches.

Spirogyra (option 3): Spirogyra is a genus of green algae commonly found in freshwater habitats. It is characterized by its spiral chloroplasts. While Spirogyra does contain some protein, it is primarily known for its high carbohydrate content, especially in the form of starch. It is not considered a significant source of protein compared to Spirulina.

Stigonema (option 4): Stigonema is another genus of cyanobacteria found in freshwater and terrestrial habitats. Like Scytonema, Stigonema has ecological importance due to its role in nitrogen fixation and biofilm formation. However, it is not recognized for having a high protein content.

3. Glycolysis is also known as

(1) Gluconeogenesis
(2) EMP Pathway
(3) Hexose monophosphate shunt
(4) Photorespiration
(5) None of these

ans:- (2) EMP Pathway

Explanation:

Glycolysis is the metabolic pathway that breaks down glucose to pyruvate, producing ATP and NADH in the process. It occurs in the cytoplasm of cells and is the first step in cellular respiration. Glycolysis is also referred to as the Embden-Meyerhof-Parnas (EMP) pathway after the scientists who elucidated its steps.

Here’s a brief overview of the other terms to explain why they are not synonymous with glycolysis:

Gluconeogenesis (option 1): This is the metabolic process by which glucose is synthesized from non-carbohydrate precursors such as lactate, glycerol, and amino acids. It is essentially the reverse of glycolysis, occurring mainly in the liver and kidneys.
Hexose monophosphate shunt (option 3): Also known as the pentose phosphate pathway (PPP), this pathway operates parallel to glycolysis and serves to produce NADPH and ribose-5-phosphate for nucleotide synthesis. It is not involved in the breakdown of glucose for energy production like glycolysis.
Photorespiration (option 4): This is a process in plants where the enzyme Rubisco oxygenates RuBP, leading to a wasteful pathway that reduces the efficiency of photosynthesis. It occurs in the presence of light and is part of the photosynthetic cycle, not related to glycolysis.

4. The rate of photosynthesis is higher in light.

(1) White
(2) Red
(3) Green
(4) Blue
(5) None of these

ans:- (1) White

Explanation:

White light contains all wavelengths of the visible spectrum, including those that are most effectively absorbed by chlorophyll and other pigments involved in photosynthesis. This comprehensive spectrum ensures that the plant receives the optimal range of wavelengths for maximum photosynthetic efficiency.

Here’s a more detailed look at the other options:

Red light (option 2): Red light is very effective for photosynthesis because chlorophyll absorbs it efficiently. However, while red light alone can drive a high rate of photosynthesis, it is not as effective as white light, which includes all colors.
Green light (option 3): Green light is the least effective for photosynthesis because it is mostly reflected by plants, which is why they appear green. Chlorophyll absorbs green light poorly.
Blue light (option 4): Blue light is also effective for photosynthesis as it is absorbed well by chlorophyll and carotenoids. However, similar to red light, blue light alone is less effective compared to the full spectrum provided by white light.

5. The fruit ripening hormone is

(1) Abscisic acid
(2) Cytokinin
(3) Ethylene
(4) Gibberellin
(5) None of these

ans:- (3) Ethylene

Explanation:

Ethylene is a plant hormone that plays a crucial role in the ripening of fruits. It is a simple hydrocarbon gas (C₂H₄) that acts as a signaling molecule to trigger and regulate various processes in plants, including the ripening of fruits. When ethylene is produced, it initiates a series of biochemical and physiological changes that result in the softening, color change, and sweetening of the fruit.

Here’s a brief overview of the other hormones and their primary functions:

Abscisic acid (option 1): This hormone primarily functions in stress responses, such as closing stomata during drought conditions, and in seed dormancy.
Cytokinin (option 2): Cytokinins are involved in cell division and growth, and they delay aging in leaves. They promote cell division and the formation of shoots.
Gibberellin (option 4): Gibberellins are involved in promoting stem elongation, seed germination, and flowering. They help in breaking dormancy in seeds and buds.

6. The largest herbarium in India is located at

(1) New Delhi
(2) Dehradun
(3) Kolkata
(4) Pune
(5) None of these

ans:- (3) Kolkata

Explanation:

The largest herbarium in India is the Central National Herbarium (CNH), which is part of the Botanical Survey of India (BSI). It is located in Kolkata (formerly Calcutta) at the Acharya Jagadish Chandra Bose Indian Botanic Garden in Shibpur, Howrah, a suburb of Kolkata. The CNH houses a vast collection of plant specimens and is a crucial center for botanical research and taxonomy in India.

Here’s a brief look at the other locations mentioned:

New Delhi (option 1): New Delhi is the capital of India and hosts several scientific institutions, but it does not have the largest herbarium in the country.
Dehradun (option 2): Dehradun is known for the Forest Research Institute (FRI), which has its own herbarium, but it is not the largest in India.
Pune (option 4): Pune has several botanical gardens and research institutions, but it does not house the largest herbarium.

7. International Rice Research Institute is in

(1) Hyderabad
(2) Cuttack
(3) Kenya
(4) Manila
(5) None of these

ans:- (4) Manila

Explanation:

The International Rice Research Institute (IRRI) is headquartered in Los Baños, Laguna, which is near Manila in the Philippines. IRRI is a major agricultural research center dedicated to the study and development of rice varieties and rice cultivation techniques to improve the yield and sustainability of rice farming worldwide.

Here’s a brief overview of the other locations mentioned:

Hyderabad (option 1): Hyderabad is a major city in India known for its biotechnology and agricultural research institutes, such as the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), but it is not the location of IRRI.
Cuttack (option 2): Cuttack in India hosts the Central Rice Research Institute (CRRI), now known as the National Rice Research Institute (NRRI), but this is different from IRRI.
Kenya (option 3): Kenya is a country in Africa with various agricultural research institutions, but it is not the location of IRRI.

8. Obligate anaerobic bacteria can

(1) grow without oxygen and produce high energy
(2) grow without oxygen and produce low energy
(3) have a fermentative metabolism and a respiratory chain
(4) grow with or without oxygen and produce medium energy
(5) None of these

ans:- (2) grow without oxygen and produce low energy

Explanation:

Obligate anaerobic bacteria are organisms that can only grow in the absence of oxygen. They lack the necessary enzymes to utilize oxygen for energy production. Instead, they rely on anaerobic metabolic pathways such as fermentation to generate energy. These pathways typically produce lower amounts of energy compared to aerobic respiration.

Here’s a brief explanation of the other options:

Option 1: This statement is incorrect because obligate anaerobes cannot produce high energy in the absence of oxygen.
Option 3: This statement is incorrect because obligate anaerobes do not possess a respiratory chain since they cannot use oxygen as a terminal electron acceptor.
Option 4: This statement is incorrect because obligate anaerobes cannot grow in the presence of oxygen.

9. Which one of the following is the correct food chain

(1) Algae-insects-frog-peacock-snake
(2) Algae-frog insects-snake-peacock
(3) Algae frog insects-peacock-snake
(4) Algae-insects-frog snake-peacock
(5) None of these

ans:- (1) Algae – Insects – Frog – Peacock – Snake

Explanation:

In a food chain, energy and nutrients are transferred from one organism to another. Here’s a breakdown of the provided options:

Option 1: Algae are primary producers, insects consume algae, frogs eat insects, peacocks prey on frogs, and snakes consume peacocks. This sequence follows a logical flow of energy transfer from producers to consumers.
Option 2: This option is incorrect because it places insects before frogs in the food chain, which is not typical in most ecosystems.
Option 3: In this option, insects are placed before frogs, which is not consistent with typical food chain dynamics.
Option 4: This option places the snake before the peacock, which is not a common sequence in a food chain.

10. DNA and RNA are similar to each other because both

(1) have similar sugars
(2) are nucleotide polymers
(3) have similar pyrimidines
(4) are double stranded
(5) None of these

ans:- (2) are nucleotide polymers

Explanation:

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are both nucleic acids composed of nucleotide monomers. Each nucleotide consists of three components: a nitrogenous base (adenine, guanine, cytosine, thymine in DNA, and uracil in RNA), a pentose sugar (deoxyribose in DNA and ribose in RNA), and a phosphate group.

While there are differences between DNA and RNA, such as the type of sugar they contain (deoxyribose in DNA, ribose in RNA) and the presence of thymine in DNA replaced by uracil in RNA, they share the fundamental structure of being nucleotide polymers.

Here’s why the other options are incorrect:

Option 1: DNA and RNA have different sugars (deoxyribose in DNA, ribose in RNA).
Option 3: While both DNA and RNA contain pyrimidine bases (cytosine and uracil), they also contain purine bases (adenine and guanine). Additionally, DNA and RNA use slightly different pyrimidine bases (thymine in DNA, uracil in RNA).
Option 4: While DNA can form a double-stranded helix, RNA is typically single-stranded, so they are not always double-stranded.

11. A simple technique has been developed in India by using the following organisms as bio-fertilizers:

(1) Azotobacter and Rhizobium
(2) Azolla and Azotobacter
(3) Azolla and Rhizobium
(4) Azotobacter and Nostoc
(5) None of these

ans:- (2) Azolla and Azotobacter

Explanation:

Azolla is a genus of aquatic ferns that can fix atmospheric nitrogen with the help of the cyanobacteria living symbiotically within its leaves. Azotobacter is a genus of free-living nitrogen-fixing bacteria commonly found in soil.

The combination of Azolla and Azotobacter can provide a sustainable and eco-friendly source of nitrogen for agricultural crops. Azolla can fix nitrogen from the atmosphere, and Azotobacter can enhance soil fertility by fixing additional nitrogen and promoting plant growth.

Here’s why the other options are incorrect:

Option 1: Rhizobium is a nitrogen-fixing bacterium that forms symbiotic relationships with leguminous plants, not Azotobacter.
Option 3: While both Azolla and Rhizobium are used as bio-fertilizers, they are not typically used together in the same technique.
Option 4: Nostoc is another genus of nitrogen-fixing cyanobacteria, but it is not typically used in combination with Azotobacter for bio-fertilization in India.

12. A sclerotium refers to a modified mycelium which is

(1) an underground structure
(2) a food storing organ
(3) a conidial type
(4) a hard resting body
(5) None of these

ans:- (4) a hard resting body

Explanation:

A sclerotium is a specialized fungal structure consisting of a compact mass of hyphae. It serves as a survival structure for fungi, allowing them to withstand adverse environmental conditions such as drought or extreme temperatures. Sclerotia are often hardened and can remain dormant for extended periods until favorable conditions for growth return.

Here’s why the other options are incorrect:

Option 1: While sclerotia can be found underground in some fungi, they are not exclusively underground structures.
Option 2: Sclerotia can store nutrients to some extent, but their primary function is not as a food-storing organ.
Option 3: Sclerotia are not a type of conidium (asexual spore) but rather a distinct fungal structure.

13. In paddy, the type of inflorescence is said to be

(1) Raceme
(2) Panicle
(3) Thyrsus
(4) Cyathium
(5) None of these

ans:- (2) Panicle

Explanation:

A panicle is a type of inflorescence in which the main axis is branched, with each branch bearing smaller branches or spikelets. This arrangement is characteristic of grasses, including rice (paddy). In the case of rice plants, the panicle consists of spikelets, which are the basic units of the inflorescence.

Here’s a brief explanation of the other options:

Raceme (option 1): In a raceme inflorescence, the main axis bears stalked flowers along its length, with the youngest flowers at the top.
Thyrsus (option 3): A thyrsus is a dense, compact, and often conical inflorescence with a main axis bearing lateral branches, often found in certain flowering plants but not in paddy.
Cyathium (option 4): A cyathium is a specialized inflorescence found in plants of the genus Euphorbia, characterized by a cup-like structure with reduced flowers enclosed within.

14. Botanical name of Pearl millet (Bajra) is

(1) Avena sativa
(2) Zea mays
(3) Eleusine coracana
( 4) Pennisetum typhoides
(5) None of these

ans:- (4) Pennisetum typhoides

Explanation:

Pearl millet, commonly known as Bajra, has the botanical name Pennisetum glaucum (synonymous with Pennisetum typhoides). It belongs to the family Poaceae (the grass family).

Here’s a brief explanation of the other options:

Avena sativa (option 1): Avena sativa refers to oats, not pearl millet.
Zea mays (option 2): Zea mays is the scientific name for maize or corn, not pearl millet.
Eleusine coracana (option 3): Eleusine coracana is the botanical name for finger millet, also known as ragi or nachni, which is different from pearl millet.

15. Which is the matching set in classification?

(1) Neries, planaria, round-worm, earthworm
(2) Millipede, crab, centipede, cockroach
(3) Starfish, jellyfish, cuttle-fish, octopus
(4) Sea-urchin, lobster, leech, locust
(5) None of these

ans:- (1) Neries, planaria, round-worm, earthworm

Explanation:

The organisms listed in option (1) belong to the phylum Annelida, which consists of segmented worms. Specifically:

Neries likely refers to “Nereis,” a genus of marine polychaete worms.
Planaria refers to flatworms of the class Turbellaria.
Roundworm typically refers to nematodes, which are also known as roundworms and belong to the phylum Nematoda.
Earthworm refers to earthworms, which belong to the class Clitellata within the phylum Annelida.

Here’s a brief explanation of why the other options are incorrect:

Option (2): The organisms listed belong to different classes and phyla, including Arthropoda (millipede, centipede, cockroach) and Crustacea (crab). They do not form a matching set within a single taxonomic group.
Option (3): The organisms listed belong to different classes and phyla, including Echinodermata (starfish), Cnidaria (jellyfish), Mollusca (cuttlefish), and Cephalopoda (octopus). They do not form a matching set within a single taxonomic group.
Option (4): The organisms listed belong to different classes and phyla, including Echinodermata (sea-urchin), Crustacea (lobster), Annelida (leech), and Insecta (locust). They do not form a matching set within a single taxonomic group.

16. The insects excrete in the form of uric acid because

(1) most of them are terrestrial
(2) the circulatory system is open
(3) the blood is colourless
(4) most of them are aquatic
(5) None of these

ans:- (1) most of them are terrestrial

Explanation:

Insects, being primarily terrestrial organisms, face challenges in conserving water and eliminating nitrogenous wastes. Uric acid is the least toxic and most water-conserving form of nitrogenous waste among terrestrial animals. It is relatively insoluble in water and can be excreted with minimal water loss, making it an efficient adaptation for organisms living in dry environments.

Here’s why the other options are incorrect:

Option 2: The type of circulatory system (open or closed) is not directly related to the excretory product of insects.
Option 3: The color of blood is not directly related to the excretory product of insects.
Option 4: Insects excrete uric acid primarily because they are terrestrial, not because they are aquatic.

17. Measurement of the rate of oxygen consumption in unit volume of water over a period of time is carried out to determine

(1) Fermentation
(2) Biogas generation
(3) Biosynthetic pathway
(4) Biological oxygen demand
(5) None of these

ans:- (4) Biological oxygen demand

Explanation:

Biological oxygen demand (BOD) is a measure of the amount of dissolved oxygen (DO) consumed by aerobic microorganisms in water while they decompose organic matter under aerobic conditions. It is an important parameter used to assess the quality of water in terms of organic pollution and the degree of oxygen depletion.

Here’s a brief overview of the other options:

Fermentation (option 1): Fermentation is a metabolic process that occurs in the absence of oxygen, producing energy through the breakdown of organic compounds.
Biogas generation (option 2): Biogas generation involves the anaerobic decomposition of organic matter by microorganisms to produce methane and carbon dioxide, typically in a biogas digester.
Biosynthetic pathway (option 3): Biosynthetic pathways are metabolic pathways involved in the synthesis of complex molecules from simpler ones, typically requiring energy input.

18. Biosphere is made up of

(1) organism
(2) organism and lithosphere
(3) organism, lithosphere and atmosphere
(4) organism, lithosphere, atmosphere & hydrosphere
(5) None of these

ans:- (4) organism, lithosphere, atmosphere & hydrosphere

Explanation:

The biosphere is the global sum of all ecosystems and includes all life forms and their interactions with the Earth’s lithosphere (land), atmosphere (air), and hydrosphere (water). It encompasses all living organisms and the environments in which they live, integrating the components of the Earth’s surface and the physical processes that occur within and between these components.

Here’s a brief explanation of why the other options are incorrect:

Option 1: While organisms are a part of the biosphere, the biosphere also includes non-living components like the lithosphere, atmosphere, and hydrosphere.
Option 2: This option is incomplete as it does not include the atmosphere and hydrosphere.
Option 3: This option is also incomplete as it does not include the hydrosphere.

19, Sudden mass death of fishes from oxygen depletion is more likely in the

(1) Eutrophic lakes
(2) Oxalotrophic lakes
(3) Oligotrophic lakes
(4) Mesotrophic lakes
(5) None of these

ans:- (1) Eutrophic lakes

Explanation:

Eutrophic lakes are characterized by high levels of nutrients, particularly nitrogen and phosphorus, which lead to excessive growth of algae and other aquatic plants. When these plants and algae die, their decomposition by bacteria consumes a significant amount of oxygen, leading to oxygen depletion, or hypoxia. This process can cause sudden mass deaths of fish and other aquatic organisms due to lack of available oxygen.

Here’s a brief explanation of the other options:

Oxalotrophic lakes (option 2): This term is not commonly used in limnology. It might be a confusion with “alkalotrophic” or “dystrophic,” which have different meanings and are not directly related to sudden oxygen depletion.
Oligotrophic lakes (option 3): These lakes have low nutrient levels and typically have high oxygen levels throughout the water column, making them less likely to experience sudden oxygen depletion.
Mesotrophic lakes (option 4): These lakes have intermediate levels of nutrients and are less prone to the extreme conditions of eutrophic lakes. They can experience oxygen depletion, but it is not as common or severe as in eutrophic lakes.

20. The sanctuary having maximum number of rare animals is

(1) Kaziranga National Park
(2) Corbett National Park
(3) Manas National Park
(4) Dudhwa National Park
(5) None of these

ans:- (3) Manas National Park

Explanation:

Manas National Park, located in Assam, India, is known for its rich biodiversity and is a UNESCO World Heritage Site. It hosts a significant number of rare and endangered species, including the Assam roofed turtle, hispid hare, golden langur, pygmy hog, and Indian rhinoceros. It is also a tiger and elephant reserve, making it one of the most important habitats for rare wildlife.

Here’s a brief explanation of the other options:

Kaziranga National Park (option 1): Located in Assam, this park is famous for its large population of Indian rhinoceroses but does not have as many rare species as Manas National Park.
Corbett National Park (option 2): Located in Uttarakhand, it is renowned for its tiger population but does not have the same level of biodiversity in terms of rare species as Manas National Park.
Dudhwa National Park (option 4): Located in Uttar Pradesh, this park has a variety of wildlife but is not known to have the maximum number of rare animals compared to Manas National Park.

21. The famous Chipko Movement’ is associated with

(1) Sunderlal Bahuguna
(2) Jawaharlal Nehru
(3) None of these
(4) Indira Gandhi
(5) H.N. Bahuguna

ans:- (1) Sunderlal Bahuguna

Explanation:

The Chipko Movement, which began in the 1970s in India, was a forest conservation movement where villagers, especially women, hugged trees to prevent them from being cut down. The movement aimed to protect the environment and promote sustainable forest management practices.

Sunderlal Bahuguna was a prominent environmentalist and one of the leading figures associated with the Chipko Movement. He played a significant role in spreading awareness about the importance of trees and forests and advocated for the rights of local communities in forest conservation.

Here’s a brief explanation of why the other options are incorrect:

Jawaharlal Nehru (option 3): He was the first Prime Minister of India and was not associated with the Chipko Movement.
Indira Gandhi (option 2): She was the Prime Minister of India during the time of the Chipko Movement but was not directly involved in the movement.
H.N. Bahuguna (option 4): Hemwati Nandan Bahuguna was an Indian politician but was not associated with the Chipko Movement.

22. Red data book is famous for

(1) Extinct animals
(2) Endangered animals and plants
(3) Endangered animals
(4) Important wildlife

ans:- (2) Endangered animals and plants

Explanation:

The Red Data Book, published by the International Union for Conservation of Nature (IUCN), is a comprehensive catalog of the conservation status of plant and animal species worldwide. It classifies species into categories such as endangered, critically endangered, vulnerable, extinct, and others based on their risk of extinction. The primary aim of the Red Data Book is to provide information on the status of various species to aid in conservation efforts and raise awareness about biodiversity loss.

Here’s a brief explanation of why the other options are less accurate:

Extinct animals (option 1): While the Red Data Book includes extinct species, its primary focus is on endangered and threatened species.
Endangered animals (option 3): The book does cover endangered animals, but it also includes endangered plants, making option (2) more comprehensive.
Important wildlife (option 4): This option is too broad and does not specifically emphasize the focus on endangered and threatened species.

23. Bottom laver of deep fresh water habitat is

(1) Hypolimnion
(2) Epilimnion
(3) Thermocline
(4) Metalimnion
(5) None of these

ans:- (1) Hypolimnion

Explanation:

In a stratified freshwater body such as a deep lake, the water column is typically divided into distinct thermal layers:

Hypolimnion (option 1): This is the bottom layer of the water body, which is colder and denser than the layers above. It is isolated from the surface and does not mix with the warmer, upper layers during stratification. This layer can often have low oxygen levels because it is cut off from atmospheric oxygen and primary production by phytoplankton.
Epilimnion (option 2): This is the topmost layer of water, which is warmest and most affected by sunlight and wind. It is well-oxygenated and supports most of the lake’s biological activity.
Thermocline (option 3): Also known as the metalimnion, this is the middle layer where there is a rapid change in temperature with depth. It acts as a barrier between the warmer epilimnion above and the colder hypolimnion below.

24. The International Convention on Biological Diversity was ratified in the year

(1) 1971
(2) 1994
(3) 1973
(4) 1990
(5) None of these

ans:- (2) 1994

Explanation:

The Convention on Biological Diversity (CBD) was opened for signature at the Earth Summit in Rio de Janeiro on June 5, 1992, and it entered into force on December 29, 1993. Ratification by the required number of countries took place in 1994, making this the year it was officially ratified and came into force.

Here’s a brief overview of why the other options are incorrect:

1971 (option 1): This predates the drafting and signing of the CBD.
1990 (option 4): This was prior to the 1992 Earth Summit where the CBD was first introduced.
1973 (option 3): This is not related to the timeline of the CBD.

25. Which is considered as bio-logical paradise in India

(1) Gulf of Mannar
(2) Nilgiri Bioreserve
(3) Sundarbans
(4) Nanda Devi

ans:- (2) Nilgiri Bioreserve

Explanation:

The Nilgiri Biosphere Reserve, located in the Western Ghats of southern India, is known for its rich biodiversity and is often referred to as a “biological paradise.” It encompasses diverse habitats ranging from tropical rainforests to montane grasslands and supports a wide variety of flora and fauna, including many endemic and endangered species.

Here’s a brief explanation of the other options:

Gulf of Mannar (option 1): This is a marine biosphere reserve located in the southeastern part of India, known for its coral reefs and marine biodiversity but is not commonly referred to as a biological paradise.
Sundarbans (option 3): This is a mangrove area in the delta region of the Padma, Meghna, and Brahmaputra river basins. It is known for its mangrove forests and the Royal Bengal Tiger but is typically not referred to as a biological paradise.
Nanda Devi (option 4): This is a national park and biosphere reserve in the Indian Himalayas, known for its alpine flora and fauna. While it is a UNESCO World Heritage Site, it is not typically labeled as a biological paradise in the same way as the Nilgiri Biosphere Reserve.

26. National Bureau of Fish Genetic Resources [NBFGR) is located in

(1) Chennai
(2) New Delhi
(3) Lucknow
(4)Bangalore
(5) None of these

ans:- (3) Lucknow

Explanation:

The National Bureau of Fish Genetic Resources (NBFGR) is a premier institution in India dedicated to the conservation and management of fish genetic resources. It is located in Lucknow, Uttar Pradesh.

Here’s why the other options are incorrect:

Chennai (option 1): This is not the location of NBFGR.
New Delhi (option 2): While New Delhi is the capital of India and hosts many important institutions, it is not the location of NBFGR.
Bangalore (option 4): Bangalore is known for various research institutions, but it is not the location of NBFGR.

27. Which of these is often called as ‘cell organiser”?

(1) Nucleus
(2) Centriole
(3) Nucleplus
(4) Ribosome
(5) None of these

ans:- (2) Centriole

Explanation:

Centrioles are often referred to as ‘cell organizers’ because they play a crucial role in the organization of microtubules in the cell. During cell division, centrioles help in the formation of the spindle fibers that separate chromosomes. They are also involved in the organization of the cytoskeleton, which maintains the cell’s shape and enables various cellular movements.

Here’s a brief explanation of the other options:

Nucleus (option 1): The nucleus is the control center of the cell, containing the genetic material and coordinating activities such as growth and reproduction, but it is not typically referred to as the ‘cell organizer’.
Nucleolus (option 3): The nucleolus is a region within the nucleus responsible for ribosome production, but it is not referred to as the ‘cell organizer’.
Ribosome (option 4): Ribosomes are responsible for protein synthesis, but they are not considered the ‘cell organizer’.

28. The powerhouse of the cell is

(1) Nucleus
(2) Ribosome
(3) Mitochondria
(4) Lysosome
(5) None of these

ans:- (3) Mitochondria

Explanation:

Mitochondria are often referred to as the “powerhouses” of the cell because they are responsible for generating most of the cell’s energy in the form of adenosine triphosphate (ATP) through the process of cellular respiration. Mitochondria have their own DNA and ribosomes, indicating their evolutionary origin from symbiotic bacteria. They are found in the cytoplasm of eukaryotic cells and play a critical role in metabolism and energy production.

Here’s a brief explanation of the other options:

Nucleus (option 1): The nucleus contains the cell’s genetic material and controls gene expression, but it is not primarily responsible for energy production.
Ribosome (option 2): Ribosomes are cellular organelles involved in protein synthesis, not energy production.
Lysosome (option 4): Lysosomes are involved in intracellular digestion and waste removal, not energy production.

29. Hardness of woody tissue is due to

(1) Silica
(4) Suberin
(2) Lignin
(3) Cellulose
(5) None of these

ans:- (2) Lignin

Explanation:

Lignin is a complex organic polymer that provides structural support and rigidity to woody plants. It is deposited in the cell walls of certain plant tissues, especially in the secondary cell wall of xylem cells. Lignin acts as a cementing material, binding together cellulose fibers and other components of the cell wall. It adds strength, rigidity, and impermeability to water, contributing to the hardness and durability of woody tissues such as wood.

Here’s a brief explanation of the other options:

Silica (option 1): Silica is not a major component of woody tissue and is more commonly found in grasses and certain herbaceous plants.
Suberin (option 4): Suberin is a waxy substance found in the cork layer of bark and in the Casparian strip of plant roots. While it contributes to the impermeability of these tissues, it is not primarily responsible for the hardness of woody tissue.
Cellulose (option 3): Cellulose is a structural polysaccharide that forms the primary component of plant cell walls, providing tensile strength, but it is not primarily responsible for the hardness of woody tissue.

30. Pea seeds will germinate best if soaked in a jar containing

(1) H
(2) H₂O
(3) N
4) CO,
(5) None of these

ans:- (2) Water (H₂O)

Explanation:

Seeds require water to initiate the germination process. When seeds are soaked in water, it triggers the rehydration of the seed tissues, activating enzymes involved in metabolism and breaking down stored nutrients to provide energy for growth. This process softens the seed coat and allows the embryonic plant to emerge from dormancy and begin to grow.

Here’s a brief explanation of the other options:

Hydrogen (H) (option 1): Hydrogen gas is not suitable for soaking seeds and promoting germination.
Nitrogen (N) (option 3): Nitrogen gas is not suitable for soaking seeds and promoting germination.
Carbon monoxide (CO) (option 4): Carbon monoxide gas is toxic to plants and is not suitable for promoting germination.

31. The shape of the growth curve is usually

(1) Inverted bell
(2) Linear
(3) Sigmoid
(4) Zig-Zag
(5) None of these

ans:- (3) Sigmoid

Explanation:

In biology and ecology, growth curves are often sigmoidal (S-shaped) in shape. This means that initially, the growth is slow, then accelerates, and finally, it slows down as it approaches a maximum value. This type of curve is typical for many biological processes, including population growth, bacterial growth, and the growth of individual organisms.

Here’s a brief explanation of the other options:

Inverted bell (option 1): This shape is not commonly associated with growth curves in biology.
Linear (option 2): Linear growth implies a constant rate of increase over time, which is not typically observed in biological growth processes.
Zig-zag (option 4): Zig-zag growth does not describe a specific shape and is not commonly used to describe growth curves in biology.

32. The forces that can change the frequency of an allele in a population are

(1) forward mutation, gene conversion, neutral evolution and recombination
(2) selection, mutagenesis, migration, inbreeding and random genetic drift
(3) dominance, family selection, fitness and diversification
(4) gene interaction, gene transfer, gene mutation and outbreeding

ans:- (2) selection, mutagenesis, migration, inbreeding and random genetic drift

Explanation:

These forces are fundamental to understanding how allele frequencies change within populations over time:

Selection: Natural selection acts on the variation within a population, favoring certain alleles that confer an advantage in a given environment.
Mutagenesis: Mutations introduce new alleles into a population, altering allele frequencies.
Migration: The movement of individuals between populations can introduce new alleles or alter existing allele frequencies.
Inbreeding: Inbreeding increases the frequency of homozygotes in a population, potentially leading to changes in allele frequencies and the expression of recessive alleles.
Random genetic drift: Random genetic drift is the change in allele frequencies due to chance events, especially in small populations where genetic diversity is reduced.

Here’s a brief explanation of why the other options are incorrect:

Option 1: While some of these processes can influence allele frequencies (e.g., recombination), they are not as directly involved in changing allele frequencies within a population.
Option 3: These factors may affect the expression of alleles within individuals but are not direct mechanisms for changing allele frequencies at the population level.
Option 4: Gene interaction, transfer, and mutation may influence genetic variation within a population, but they are not forces that directly change allele frequencies across a population.

33. The anticodon region is present in

(1)-RNA
(2) hn-RNA
(3) m-RNA
(4) t-RNA
(5) None of these

ans:- (4) t-RNA (transfer RNA)

Explanation:

Transfer RNA (tRNA) molecules are responsible for bringing amino acids to the ribosome during protein synthesis. Each tRNA molecule has an anticodon region, which is a sequence of three nucleotides complementary to a specific codon on the mRNA (messenger RNA). The anticodon region of tRNA base-pairs with the codon on the mRNA, ensuring that the correct amino acid is added to the growing polypeptide chain.

Here’s a brief explanation of the other options:

RNA (option 1): While RNA molecules are involved in various cellular processes, the term “anticodon region” specifically refers to a feature of tRNA molecules.
hn-RNA (option 2): Heterogeneous nuclear RNA (hnRNA) is a precursor to mRNA and undergoes processing to become mature mRNA in eukaryotic cells. It does not have an anticodon region.
m-RNA (option 3): Messenger RNA (mRNA) carries the genetic information from DNA to the ribosome, where it is translated into protein. mRNA contains codons that are recognized by tRNA molecules during translation, but it does not have an anticodon region.

34. in reptiles and birds, nitrogen is excreted in the form of

(1) urea
(2) Uric acid
(3) Ammonia

ans:- (2) Uric acid

Explanation:

Reptiles and birds, being primarily terrestrial animals, face challenges in conserving water and eliminating nitrogenous wastes. They excrete nitrogenous waste in the form of uric acid, which is relatively insoluble in water and can be excreted with minimal water loss. This adaptation is particularly advantageous for these animals in arid environments where water conservation is critical.

Here’s a brief explanation of the other options:

Ammonia (option 3): Ammonia is highly toxic and requires a large amount of water for dilution and excretion. It is the primary nitrogenous waste excreted by aquatic animals, not by terrestrial reptiles and birds.

35. Which of the following techniques are used in assaying monoclonal antibodies?

(1) Flow cytometry
(2) PAGE
(3) HPLC
(4) Scintillation counter
(5) None of these

ans:- (3) HPLC (High-Performance Liquid Chromatography)

Explanation:

High-Performance Liquid Chromatography (HPLC) is a widely used analytical technique for separating, identifying, and quantifying components in a mixture. In the context of assaying monoclonal antibodies, HPLC can be used to analyze the purity, size, and structure of the antibody molecules. It allows for the separation of different components based on their physicochemical properties, such as size, charge, and hydrophobicity.

Here’s a brief explanation of the other options:

Flow cytometry (option 1): Flow cytometry is a technique used to analyze and sort cells based on their properties, such as size, complexity, and fluorescence. While it can be used in immunology to analyze cell surface markers and protein expression, it is not typically used for assaying monoclonal antibodies themselves.
PAGE (Polyacrylamide Gel Electrophoresis) (option 2): PAGE is a technique used to separate proteins based on their size and charge. While it can be used to analyze proteins, including antibodies, it is not as commonly used for assaying monoclonal antibodies as HPLC.
Scintillation counter (option 4): A scintillation counter is used to measure radioactivity in samples by detecting the light produced during radioactive decay. While radioisotopes can be used in certain assays involving antibodies, the scintillation counter is not specifically used for assaying monoclonal antibodies.

36. Which of the following synthetic polypeptides will form a triple helix?

(1) (Pro-Glyin
(2) (Phe-Gly-Gly)n
(3) (Pro-Gly-Glyn
(4) (Gly-Pro-Pro-Glyn
(5) None of these

ans:- (4) (Gly-Pro-Pro-Gly)n

Explanation:

A triple helix structure is a characteristic feature of collagen, the most abundant protein in mammals. Collagen is composed of three polypeptide chains that are rich in glycine (Gly), proline (Pro), and hydroxyproline (Hyp). The repeating sequence Gly-Pro-Pro is crucial for the stability and formation of the collagen triple helix structure. The Gly residues are required for the tight packing of the three chains, while the Pro residues provide kinks that allow the helix to twist.

Here’s a brief explanation of the other options:

(Pro-Gly)n (option 1): This sequence lacks the required Gly-Pro-Pro motif and is not likely to form a triple helix.
(Phe-Gly-Gly)n (option 2): Phenylalanine (Phe) is not typically found in collagen and does not contribute to triple helix formation.
(Pro-Gly-Gly)n (option 3): While this sequence contains Gly and Pro, it lacks the critical Gly-Pro-Pro motif required for triple helix formation.

37. World Health Organisation (WHD) announced the eradication of small pox as a disease in the year

(1) 1988
(2) 1986
(3) 1977
(4) 1979

ans:- (1) 1988

Explanation:

Smallpox, a highly contagious and deadly disease caused by the variola virus, was officially declared eradicated by the World Health Organization (WHO) in 1980. This monumental achievement marked the end of a decades-long global vaccination campaign led by WHO, which involved mass vaccination efforts and surveillance to identify and contain outbreaks of the disease. The last known natural case of smallpox occurred in 1977 in Somalia, and following intensive vaccination campaigns, the disease was declared eradicated in 1980.

Here’s a brief explanation of why the other options are incorrect:

1986 (option 2): This was not the year when smallpox was declared eradicated.
1977 (option 3): While the last known natural case of smallpox occurred in 1977, it took several years of continued efforts to officially declare the disease eradicated.
1979 (option 4): This was not the year when smallpox was declared eradicated.
None of these (option 5): This option is incorrect because smallpox was indeed declared

38. A disease that attacks many in a community simultaneously is

(1) an epidemic
(2) a Nosocomial infection
(3) a secondary infection
(4) a bacteremia
(5) None of these

ans:- (1) an epidemic

Explanation:

An epidemic refers to the rapid spread of a disease to a large number of people within a specific population or geographic area. Epidemics typically involve a sudden increase in the number of cases of a particular disease beyond what is normally expected. The term is often used to describe outbreaks of infectious diseases that affect a significant proportion of the population within a defined region or community over a relatively short period of time.

Here’s a brief explanation of the other options:

Nosocomial infection (option 2): Nosocomial infections are infections that are acquired in a hospital or healthcare facility, often due to exposure to pathogens in healthcare settings.
Secondary infection (option 3): A secondary infection occurs after an initial infection, often as a result of a weakened immune system or complications from the primary infection.
Bacteremia (option 4): Bacteremia refers to the presence of bacteria in the bloodstream and can lead to systemic infections if not promptly treated.

39. The term “Microbiology” was coined by

(1) Antonie van Leeuwenhoes
(2) Robert Koch
(3) Louis Pasteur
(4) Julius Richard Petri
(5) None of these

ans:- (1) Antonie van Leeuwenhoek

Explanation:

Antonie van Leeuwenhoek, a Dutch scientist and tradesman, is often credited as the father of microbiology. He was the first person to observe and describe microorganisms using a single-lens microscope of his own design. Although he did not coin the term “microbiology” himself, his groundbreaking work laid the foundation for the field.

Here’s a brief explanation of the other options:

Robert Koch (option 2): Robert Koch was a German physician and microbiologist known for his contributions to the germ theory of disease and his work on identifying the causative agents of specific diseases, such as anthrax and tuberculosis.
Louis Pasteur (option 3): Louis Pasteur was a French chemist and microbiologist renowned for his discoveries in vaccination, pasteurization, and fermentation. While he made significant contributions to microbiology, he did not coin the term “microbiology.”
Julius Richard Petri (option 4): Julius Richard Petri was a German bacteriologist who invented the Petri dish, a common laboratory tool used for culturing microorganisms. He did not coin the term “microbiology.”

40. Tumour-causing viruses are known as

(1) Oncogenic viruses
(2) Para viruses
(3) Tungro viruses
(4) Variola viruses
(5) None of these

ans :- (1) Oncogenic viruses

Explanation:

Oncogenic viruses are viruses that are capable of causing tumors or cancer in their host organisms. These viruses can integrate their genetic material into the host cell’s genome, leading to uncontrolled cell division and tumor formation. Examples of oncogenic viruses include human papillomavirus (HPV), Epstein-Barr virus (EBV), hepatitis B virus (HBV), and human T-cell lymphotropic virus (HTLV).

Here’s a brief explanation of the other options:

Paraviruses (option 2): There is no widely recognized category of viruses known as “paraviruses.” It is possible that this term refers to viruses that infect parasites, but it is not commonly used in the context of tumour-causing viruses.
Tungro viruses (option 3): Tungro viruses are plant viruses that infect rice plants and cause diseases known as tungro diseases. They are not associated with tumor formation in animals.
Variola viruses (option 4): Variola viruses are the causative agents of smallpox, a disease that has been eradicated from the human population. While variola viruses cause severe illness, they are not known to cause tumors.

41. fled orange colour in saffron is due to

(1) Xanthophyll
(2) Chlorophyll
(3) Crocetin
(4) Polyphenols
(5) None of these

ans:- (3) Crocetin

Explanation:

Crocetin is a carotenoid compound responsible for the characteristic red-orange color of saffron. Saffron is derived from the stigma of the Crocus sativus flower, and crocetin is one of the main compounds responsible for its color, flavor, and aroma. It is a water-soluble carotenoid that contributes to the unique sensory properties of saffron when used in cooking and traditional medicine.

Here’s a brief explanation of the other options:

Xanthophyll (option 1): Xanthophylls are yellow pigments found in plants and algae. While saffron contains some xanthophylls, they are not responsible for the red-orange color of saffron.
Chlorophyll (option 2): Chlorophyll is a green pigment found in plants that is responsible for photosynthesis. It is not present in significant amounts in saffron and is not responsible for its color.
Polyphenols (option 4): Polyphenols are a diverse group of compounds found in plants, including saffron. While they may contribute to the overall chemical composition of saffron, they are not responsible for its red-orange color.

42. Choose the correct answer. Beaten rice in ase known as

(1) Flaked rice
(2) Polished rice
(3) Puffed rice
(4) Popped rice
(5) None of these

ans:- (1) Flaked rice

Explanation:

Beaten rice, also known as flattened rice or pressed rice, is a type of rice that has been flattened into flat, light flakes. It is a common ingredient in many Asian cuisines, particularly in South Asia and Southeast Asia. Beaten rice is often used to make snacks, breakfast dishes, and desserts.

Here’s a brief explanation of the other options:

Polished rice (option 2): Polished rice refers to rice grains that have had their outer husks, bran, and germ removed, leaving behind the starchy endosperm. It is not the same as beaten rice.
Puffed rice (option 3): Puffed rice is rice grains that have been heated under high pressure to expand and form puffed, crunchy kernels. It is not the same as beaten rice.
Popped rice (option 4): Popped rice refers to rice grains that have been heated until they “pop” open, similar to popcorn. It is not the same as beaten rice.

43. Spice bag is usually used in the processing of

(1) Sauce
(2) Jam
(3) Pickle
(4) Nectar
(5) None of these

ans:- (3) Pickle

Explanation:

A spice bag is a small fabric pouch or sachet filled with various whole spices and herbs. It is commonly used in the preparation of pickles to infuse the pickling liquid with flavor and aroma. The spice bag allows the spices to impart their flavors to the pickling liquid without dispersing loose spices throughout the mixture, making it easier to remove them later.

Here’s a brief explanation of the other options:

Sauce (option 1): While spices may be used in sauces, a spice bag is not commonly used in sauce processing.
Jam (option 2): Spices are not typically used in the processing of jam, and a spice bag is not commonly used in jam making.
Pickle (option 3): As explained above, a spice bag is commonly used in the processing of pickles to infuse the pickling liquid with flavor.
Nectar (option 4): Spices are not commonly used in the processing of nectar, and a spice bag is not typically used in nectar production.

44. Cereals are

(1) deficient in lysine and rich in methionine
(2) rich in lysine and deficient in methionine
(3) rich in lysine and methionine
(4) deficient in lysine and methionine
(5) None of these

ans:- (4) deficient in lysine and methionine

Explanation:

Cereals, such as wheat, rice, maize (corn), and barley, are staple food crops for many people worldwide. However, they are deficient in certain essential amino acids, particularly lysine and methionine. This deficiency makes cereals incomplete protein sources, as they lack sufficient quantities of these amino acids for optimal human nutrition. Therefore, consuming cereals alongside other protein-rich foods, such as legumes, can help balance the amino acid profile of the diet.

Here’s a brief explanation of the other options:

Deficient in lysine and rich in methionine (option 1): This statement is incorrect. Cereals are deficient in both lysine and methionine.
Rich in lysine and deficient in methionine (option 2): This statement is incorrect. Cereals are deficient in both lysine and methionine.
Rich in lysine and methionine (option 3): This statement is incorrect. Cereals are deficient in both lysine and methionine.

46. Annual loss of agricultural produce in inde is more due to different factors. Find out the factors in correct sequence based on the higher degree of lossito lower degree

(1) Weeds followed by insects followed by diseases
(2) Insects followed by diseases followed by weeds
(3) Diseases followed by weeds followed by insects
(4) Weeds followed by diseases followed by insects
(5) None of these

ans:- (4) Weeds followed by diseases followed by insects

Explanation:

Weeds are one of the major factors contributing to agricultural yield losses in India. They compete with crops for nutrients, water, and sunlight, thereby reducing crop yields. Diseases, caused by pathogens such as fungi, bacteria, and viruses, can also significantly impact crop productivity by causing wilting, rotting, and other forms of damage. Insects, including pests like aphids, beetles, and caterpillars, can cause direct damage to crops by feeding on leaves, stems, and fruits, leading to reduced yields.

Here’s a brief explanation of why the other options are incorrect:

Option 1: Weeds are typically a more significant factor than insects and diseases in terms of agricultural yield losses.
Option 2: Insects are often a more significant factor than diseases in terms of agricultural yield losses.
Option 3: Diseases are generally more significant than weeds and insects in terms of agricultural yield losses.

47. The crop grown for grain, green manure and fodder

(1) Lentil
(2) Chick pra
(3) Red gram
(4) Cow pea

ans:- (4) Cowpea

49. The machine used for dehusking of pulses is

(1) energy roll dehusker
(2) rubber roll dehusker
(3) centrifugal dehusker
(4) under runner disc sheller
(5) None of these

ans:- (2) Rubber roll dehusker

Energy roll dehusker (option 1): Energy roll dehusker is not a common machine used for dehusking of pulses. This option is incorrect.
Rubber roll dehusker (option 2): Rubber roll dehusker is the correct option. It is a widely used machine for dehusking pulses. In this machine, rubber rolls are used to exert pressure on the pulses, removing their outer husks.
Centrifugal dehusker (option 3): Centrifugal dehusker is not typically used for dehusking pulses. Centrifugal machines are often used for separating grains from their husks or for polishing rice.
Under runner disc sheller (option 4): Under runner disc sheller is a type of rice milling machine used for removing the husk from rice grains. It is not commonly used for dehusking pulses.

50. The size of a tractor tyre may be represented as

(1) section height rim width
(2) section height rim diameter
(3) section thickness rim diameter
(4) section radius x rim width
(5) None of these

ans;- (1) section height rim width

Section height rim width (option 1): This representation typically indicates the dimensions of a tire. The section height refers to the distance from the bead of the tire to the outer tread surface, and the rim width refers to the width of the wheel rim. This representation is commonly used for specifying tire sizes.
Section height rim diameter (option 2): While this representation includes the section height, it incorrectly substitutes rim diameter for rim width. The rim diameter refers to the diameter of the wheel rim, not its width.
Section thickness rim diameter (option 3): This option combines section thickness and rim diameter, which is not a standard representation for tractor tire sizes. The section thickness is not commonly used to describe tire dimensions.
Section radius x rim width (option 4): This option presents a combination of section radius and rim width. However, the section radius is not a standard measure used to describe tire sizes.

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