Free NEET Biology multiple-choice questions on Organisms and Populations. Attempt each question and reveal the answer with a full explanation.
Identify the correct sequence of embryonic development stages in humans. Zygote → Morula → Blastocyst → Gastrula Zygote → Blastocyst → Morula → Gastrula Zygote → Morula → Gastrula → Blastocyst Zygote → Gastrula → Morula → Blastocyst A biologist studied the population of rats in a barn. He found that the average natality was 250, average mortality 240, immigration 20 and emigration 30. The net increase in population is (1) 10 (2) 15 (3) 05 (4) Zero Techniques like Magnetic Resonance Imaging (MRI) use to detect pathological and physiological changes in living tissue. Strong magnetic fields and non-ionising radiations Ionising radiations and X-rays Gamma rays and magnetic fields Ultraviolet rays and sonic waves Cannabinoids are generally taken by: Inhalation and oral ingestion Injection only Snorting and smoking Topical application Big holes in 'Swiss cheese' are made by a: Bacterium producing a large amount of CO 2 Fungus releasing metabolic water Machine during sterilization Virus lyzing the cheese cells Which of the following is used in the clarification of bottled fruit juices? Pectinases and Proteases Lipases and Amylases Cellulases and Hemicellulases Streptokinases Cyclosporin A, used as an immunosuppressive agent, is produced by the fungus: Trichoderma polysporum Monascus purpureus Saccharomyces cerevisiae Aspergillus niger During secondary treatment of sewage, 'Flocs' are formed. What do these flocs consist of? Masses of bacteria associated with fungal filaments Masses of algae and protozoa Pure colonies of methanogens Solid waste materials and sand In the process of sewage treatment, the sedimented bacterial flocs are called: Activated sludge Primary sludge Effluent Tertiary sludge Methanogens, such as Methanobacterium , are commonly found in: Anaerobic sludge in sewage treatment and rumen of cattle Aerobic tanks of sewage treatment The respiratory tract of humans High temperature sulfur springs Which of the following is a free-living nitrogen-fixing bacterium found in the soil? Azotobacter Rhizobium Frankia Glomus Which of the following is the 'clot buster' enzyme produced by Streptococcus and modified by genetic engineering? Streptokinase Lipase Amylase Cyclosporin A sedentary sea anemone gets attached to the shell lining of hermit crab. The association is (1) Ectoparasitism (2) Symbiosis (3) Commensalism (4) Amensalism Which of the following is NOT a primary lymphoid organ? Spleen Bone marrow Thymus Both (b) and (c) In the life cycle of Plasmodium , the fertilization and development of the parasite take place in the: Gut of the female Anopheles mosquito Salivary glands of the female Anopheles mosquito Liver of the human host Red blood cells of the human host Which of the following microbes is used for the commercial production of citric acid? Aspergillus niger Clostridium butylicum Lactobacillus Acetobacter aceti Interferons are a type of barrier of innate immunity. Cytokine Physiological Cellular Physical Which of the following is an example of an autoimmune disease? Rheumatoid arthritis Type I Diabetes mellitus Asthma Both Rheumatoid arthritis and Type I Diabetes mellitus The diagnostic test for AIDS is whereas its confirmation is usually done by . ELISA; Western Blot Widal; ELISA Western Blot; ELISA PCR; Widal Excessive dosage of which of the following drugs causes hallucinations? Atropa belladonna and Datura Morphine and Heroin Tobacco and Alcohol Penicillin and Statins Match the organic acid with the microbe that produces it: (a) Citric acid (b) Acetic acid (c) Butyric acid (d) Lactic acid. (i) Acetobacter aceti (ii) Clostridium butylicum (iii) Aspergillus niger (iv) Lactobacillus . a-iii, b-i, c-ii, d-iv a-i, b-ii, c-iii, d-iv a-iv, b-iii, c-ii, d-i a-iii, b-iv, c-i, d-ii In a sewage treatment plant, the primary sludge is used for: Physical removal of particles Anaerobic digestion Aerobic digestion Tertiary treatment The BOD (Biochemical Oxygen Demand) test measures the rate of uptake of oxygen by microorganisms in a sample of water to oxidize: Organic matter Inorganic salts Dissolved CO 2 Pathogenic bacteria Gause's principle of competitive exclusion states that : More abundant species will exclude the less abundant species through competition. Competition for the same resources excludes species having different food preferences. No two species can occupy the same niche indefinitely for the same limiting resources. Larger organisms exclude smaller ones through competition. Which of the following helps in the absorption of phosphorus from soil by plants? Glomus Rhizobium Anabaena Azotobacter Alexander Fleming discovered Penicillin while working on which of the following bacteria? Staphylococci Streptococci Bacillus subtilis Escherichia coli Which of the following acts as a mechanical carrier for the pathogen of Amoebiasis? Houseflies Female Anopheles mosquito Female Culex mosquito Female Aedes mosquito The full potential of Penicillin as an effective antibiotic was established by which of the following scientists? Ernest Chain and Howard Florey Alexander Fleming and Ernest Chain Howard Florey and Robert Koch Louis Pasteur and Alexander Fleming Large holes in 'Swiss cheese' are due to the production of a large amount of CO 2 by which bacterium? Propionibacterium sharmanii Saccharomyces cerevisiae Lactobacillus acidophilus Leuconostoc mesenteroides In the sewage treatment plant (STP), the effluent from the primary settling tank is passed into: Large aeration tanks Anaerobic sludge digesters Settling tanks Tertiary treatment unit Microbes like Azospirillum and Azotobacter are used as biofertilisers because they: Are free-living nitrogen fixers in the soil Form symbiotic associations with legumes Increase phosphorus solubility Decompose organic matter rapidly The spleen is often referred to as a filter of the blood because it traps: Blood-borne microorganisms Excess glucose Dead white blood cells Toxic chemicals Which of the following provides 'Passive Immunity' to a person? Injection of Tetanus antitoxin Injection of weakened pathogens Naturally occurring infection Vaccination for Polio The Recombinant DNA technology has allowed the production of Antigenic polypeptides of pathogens in bacteria or yeast. The Hepatitis B vaccine is produced from: Yeast Bacteria Human serum Transgenic mice Which one of the following plants shows a very close relationship with a species of moth, where none of the two can complete its life cycle without the other? Banana Yucca Hydrilla Viola Smoking increases the concentration of in the blood, which reduces the concentration of haembound oxygen. Carbon monoxide Carbon dioxide Nitrogen dioxide Sulphur dioxide Which of the following is a characteristic symptom of 'Withdrawal Syndrome' associated with drug/alcohol dependence? Anxiety and shakiness Excessive sleep Increased appetite Lowered heart rate Use of anabolic steroids in females can lead to which of the following side effects? Masculinisation Breast enlargement Height increase Improved memory In a pond, there were 20 lotus plants last year and through reproduction, 8 new plants are added, taking the current population to 28 . What is the birth rate for this population? 0.4 offspring per lotus per year 0.8 offspring per lotus per year 2.8 offspring per lotus per year 0.28 offspring per lotus per year If an individual is born or dies, it is an individual attribute. However, if we discuss the 'Sex Ratio', it is a: Population attribute Species attribute Community attribute Ecosystem attribute A stage of suspended development entered by many zooplankton species in lakes and ponds under unfavorable conditions is called: Diapause Hibernation Aestivation Dormancy Organisms that are capable of maintaining homeostasis by physiological means, ensuring constant body temperature and osmotic concentration, are called: Regulators Conformers Partial Regulators Suspenders In population ecology, which of the following is an attribute of a population but NOT of an individual organism? Birth rate Birth Death Age Identify the correct type of age pyramid for a declining population. Urn-shaped Bell-shaped Triangular Rectangular A population has more young individuals compared to the older individuals. What would be the status of the population in the future? It will increase It will decrease It will remain stable It will first decline then stabilize Natality refers to Number of individuals leaving the habitat Birth rate Death rate Number of individuals entering a habitat Which of the following equations correctly represents the population density at time t+1 ? N t+1 = N t + [(B + I) - (D + E)] N t+1 = N t + [(B + E) - (D + I)] N t+1 = N t + [(D + E) - (B + I)] N t+1 = N t + [(B + D) - (I + E)] An age pyramid with a bell-shaped structure indicates that the population is: Stable Expanding Declining Extinct Animals have the innate ability to escape from predation. Examples for the same are given below. Select the incorrect example Colour change in chameleon Poison fangs in snakes Melanism in moths Enlargement of body size by swallowing air in puffer fish Annual migration does not occur in the case of - Salmon Siberian crane Salamander Arctic tern The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the season. What does this show? the food plants mature and die at the end of the rainy season its population growth curve is of J-type the population of its predators increases enormously S-shaped or sigmoid growth of this insect. In the mean and the median pertaining to a certain character of a population are of the same value, which of the following is most likely to occur a bi-modal distribution a T-shaped curve a skewed curve a normal distribution. A country with a high rate of population growth took measures to reduce it. The figure below shows age-sex pyramids of populations A and B twenty years apart. Select the correct interpretation about them : – "A" is the earlier pyramid and no change has occurred in the growth rate "A" is more recent shows slight reduction in the growth rate "B" is earlier pyramid and shows stabilized growth rate "B" is more recent showing that population is very young When does the growth rate of a population following the logistic model equal zero ? The logistic model is given as dN/dt = rN(1-N/K) :- (1) when N/K is exactly one. (2) when N nears the carrying capacity of the habitat. (3) when N/K equals zero. (4) when death rate is greater than birth rate. It is much easier for a small animal to run uphill than for a large animal, because :- (1) It is easier to carry a small body weight. (2) Smaller animals have a higher metabolic rate. (3) Small animals have a lower O2 requirement. (4) The efficiency of muscles in large animals is less than in the small animals. In a hypothetical population of 100 individual having ‘r’=0.5/female/year, what will be the population size in 6 years (with e = 2.72) showing exponential rate of growth? 448 1218 739 2012 Niche is the range of temperature that the organism needs to live the physical space where an organism lives all the biological factors in the organism's environment the functional role played by the organism where it lives Inspite of interspecific competition in nature, which mechanism the competing species might have evolved for their survival? Competitive release Mutualism Predation Resource partitioning Match List-I with List - II array ll List - I & List - II (a) Allen’s Rule & (i) Kangaroo rat (b) Physiological adaptation & (ii) Desert lizard (c) Behavioural adaptation & (iii) Marine fish at depth (d) Biochemical adaptation & (iv) Polar seal array Choose the correct answer from the options given below. (a) (iv) (b) (i) (c) (iii) (d) (ii) (a) (iv) (b) (i) (c) (ii) (d) (iii) (a) (iv) (b) (iii) (c) (ii) (d) (i) (a) (iv) (b) (ii) (c) (iii) (d) (i) If ‘8’ Drosophila in a laboratory population of ‘80’ died during a week, the death rate in the population is individuals per Drosophila per week. 10 1.0 zero 0.1 Match List I with List II : array ll List I (Interaction) & List II (Species A and B) A. Mutualism & I. +(A), 0(B) B. Commensalism & II. -(A), 0(B) C. Amensalism & III. +(A), -(B) D. Parasitism & IV. +(A), +(B) array Choose the correct answer from the options given below: A-IV, B-II, C-I, D-III A-IV, B-I, C-II, D-III A-IV, B-III, C-I, D-II A-III, B-I, C-IV, D-II Match List I with List II. array ll List I & List II A. Logistic growth & I. Unlimited resource availability condition B. Exponential growth & II. Limited resource availability condition C. Expanding age pyramid & III. The percent individuals of pre-reproductive age is largest followed by reproductive and post reproductive age groups D. Stable age pyramid & IV. The percent individuals of pre-reproductives and reproductive age group are same array Choose the correct answer from the options given below: A-II, B-I, C-III, D-IV A-II, B-III, C-I, D-IV A-II, B-IV, C-I, D-III A-II, B-IV, C-III, D-I Given below are two statements: Statement I: Gause’s competitive exclusion principle states that two closely related species competing for different resources cannot exist indefinitely. Statement II: According to Gause's principle, during competition, the inferior will be eliminated. This may be true if resources are limiting. In the light of the above statements, choose the correct answer from the options given below : Both Statement I and Statement II are true. Both Statement I and Statement II are false. Statement I is true but Statement II is false. Statement I is false but Statement II is true. Given below are two statements : Statement I : Fig fruit is a non-vegetarian fruit as it has enclosed fig wasps in it. Statement II : Fig wasp and fig tree exhibit mutual relationship as fig wasp completes its life cycle in fig fruit and fig fruit gets pollinated by fig wasp. In the light of the above statements, choose the most appropriate answer from the options given below : Statement I is incorrect but statement II is correct Both statement I and statement II are correct Both statement I and statement II are incorrect Statement I is correct but statement II is incorrect Consider a population of 10 million cells. Given the per-capita birth rate of 0.002 (per unit time) and the per-capita death rate of 0.002 (per unit time), the expected number of cells after 10 generations is . 1 million 5 million 10 million 100 million Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : The logistic growth model of populations is considered more realistic than the exponential growth model. Reason R : Resources are finite. In the light of the above statements, choose the most appropriate answer from the options given below : Both A and R are correct and R is the correct explanation of A Both A and R are correct but R is not the correct explanation of A A is correct but R is not correct A is not correct but R is correct Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Abingdon tortoise in Galapagos islands became extinct within a decade after goats were introduced. Reason R : Goats were more efficient at browsing than Abingdon tortoise. In the light of the above statements, choose the most appropriate answer from the options given below: Both A and R are correct and R is the correct explanation of A Both A and R are correct, but R is not the correct explanation of A A is correct but R is not correct A is not correct but R is correct Pneumatophores occur in Carnivorous plants Free-floating hydrophytes Halophytes Submerged hydrophytes Which one of the following population interactions is widely used in medical science for the production of antibiotics? Parasitism Mutualism Commensalism Amensalism In a growing population of a country, reproductive and pre-reproductive individuals are equal in number. reproductive individuals are less than the post-reproductive individuals. pre-reproductive individuals are more than the reproductive individuals. pre-reproductive individuals are less than the reproductive individuals. Which of the following is not an attribute of a population? Natality Mortality Species interaction Sex ratio Which of the following is an example of a population? All the rats in an abandoned dwelling A group of different species in a pond A single teak tree in a forest All the animals in a zoo Amensalism can be represented as: Species A (+); Species B (+) Species A (−); Species B (−) Species A (+); Species B (0) Species A (−); Species B (0) In the exponential growth equation N t = N 0 e rt , e represents The base of exponential logarithms The base of natural logarithms The base of geometric logarithms The base of number logarithms Assertion (A): A person goes to high altitude and experiences 'altitude sickness' with symptoms like breathing difficulty and heart palpitations. Reason (R): Due to low atmospheric pressure at high altitude, the body does not get sufficient oxygen. In the light of the above statements, choose the correct answer from the options given below (1) Both (A) and (R) are true but (R) is not the correct explanation of (A) (2) (A) is true but (R) is false (3) (A) is false but (R) is true (4) Both (A) and (R) are true and (R) is the correct explanation of (A) Which one of the following statements cannot be connected to Predation? It might lead to extinction of a species Both the interacting species are negatively impacted It is necessitated by nature to maintain the ecological balance It helps in maintaining species diversity in a community While explaining interspecific interaction of population, (+) sign is assigned for beneficial interaction, (−) sign is assigned for detrimental interaction and (0) for neutral interaction. Which of the following interactions can be assigned (+) for one species and (−) for another species involved in the interaction? Amensalim Commensalism Competition Predation Given below are two statements: Statement I : Gause’s ‘Competitive Exclusion Principle’ states that two closely related species competing for the same resources cannot co-exist indefinitely and competitively inferior one will be eliminated eventually. Statement II : In general, carnivores are more adversely affected by competition than herbivores. In the light of the above statements, choose the correct answer from the options given below: Both Statement I and Statement II are true. Both Statement I and Statement II are false. Statement I is correct but Statement II is false. Statement I is incorrect but Statement II is true. Match List I with List II. array ll List I; (Interacting species) & List II; (Name of interaction) A. A Leopard and a Lion in a forest/grassland & I. Competition B. A Cuckoo laying egg in a Crow’s nest & II. Brood parasitism C. Fungi and root of a higher plant in Mycorrhizae & III. Mutualism D. A cattle egret and a Cattle in a field & IV. Commensalism array Choose the correct answer from the options given below. (1) A-I, B-II, C-III, D-IV (2) A-I, B-II, C-IV, D-III (3) A-III, B-IV, C-I, D-II (4) A-II, B-III, C-I, D-IV The equation of Verhulst-Pearl logistic growth is dN dt =rN [ K-N K ] . From this equation, K indicates: Intrinsic rate of natural increase Biotic potential Carrying capacity Population density Which one of the following equations represents the Verhulst-Pearl Logistic Growth of population? dN dt =N ( r-K K ) dN dt =r ( K-N K ) dN dt =rN ( K-N K ) dN dt =rN ( N-K N ) Epiphytes that are growing on a mango branch is an example of which of the following? Amensalism Commensalism Mutualism Predation Which of the following is not true for a species - Members of a species can interbreed Variations occur among members of a species Gene flow does not occur between the populations of a species Each species is reproductively isolated from every other species. Choose the correct statements regarding population interactions between two species. A. In both parasitism and commensalism, only one species benefits and the other species is harmed. B. Both species benefit in mutualism. C. Both species benefit in commensalism. D. In parasitism, only one species benefits and the other species is harmed. E. In amensalism, one species is harmed and the other is unaffected. Choose the correct answer from the options given below: A and B only B and E only B, D and E only A and D only Which of the following equations depicts Verhulst-Pearl logistic population growth? dN dt =rN ( K-N K ) dN dt =rN ( K K-N ) dN dt =rN ( K-N N ) dN dt =rN ( K+N K ). The maximum growth rate of the human population occurred during the 20th century primarily due to: Rapid decline in death rate and maternal mortality rate Increase in the number of people of reproducible age only Decline in the birth rate Effective implementation of contraceptive methods The process of delivery of the fetus is called: Parturition Implantation Gestation Lactation The phenomenon where a small group of individuals migrates to a new area and starts a new population, with allele frequencies different from the original population, is called: Founder effect Genetic bottleneck Gene flow Adaptive radiation Genetic drift operates only in: Small isolated populations Large populations Island populations only Mendelian populations Alfred Russel Wallace, a naturalist, worked in which geographical area while arriving at similar conclusions to Darwin's regarding evolution? Malay Archipelago Galapagos Islands Australian Outback Amazon Rainforest Darwin was deeply influenced by the 'Essay on Population' written by: Thomas Malthus Alfred Wallace Lamarck Gregor Mendel What is the primary cause of 'Genetic Drift' in a population? Chance events in a small population Large scale migration Natural selection High mutation rate Genetic drift is also known as the: Sewall Wright effect Hardy-Weinberg effect Darwinian effect Lamarckian effect Praying mantis is a good example of- Mullerian mimicry Warning colouration Social insects Camouflage The 'Bottleneck Effect' is a type of genetic drift that occurs when: A population's size is drastically reduced by a natural disaster A few individuals colonize a new habitat Mutation rates suddenly increase Gene flow between two populations is maximized The imaginary line that separates the distinct flora and fauna of the Oriental region from the Australian region is known as: Wallace's Line Equator Bering Strait Tropic of Cancer Which of the following sets of diseases is caused by bacteria? Cholera and Tetanus Typhoid and Smallpox Tetanus and Mumps Herpes and Influenza Which of the following is a bioactive molecule used as an immunosuppressive agent in organ-transplant patients? Cyclosporin A Statin Streptokinase Lipase Biogas is a mixture of gases produced by microbial activity. Which of the following is the major component, making up about 50-70 % of the mixture? Methane ( CH 4 ) Carbon dioxide ( CO 2 ) Hydrogen sulfide ( H 2S ) Nitrogen ( N 2 ) Which of the following is a nitrogen-fixing aquatic fern that is often used as a biofertilizer in rice paddies? Azolla Salvinia Marsilea Equisetum Dry, scaly lesions on the skin, nails, and scalp, accompanied by intense itching, are symptoms of which disease? Ringworm Ascariasis Amoebiasis Filariasis Innate immunity is characterized by being: Non-specific and present from birth Pathogen-specific and acquired after birth Mediated only by antibodies Effective only against viruses Chronic intake of alcohol leads to severe damage of the liver, primarily due to the replacement of normal liver tissue with fibrous tissue, a condition known as: Cirrhosis Hepatitis Jaundice Emphysema In the life cycle of the malarial parasite Plasmodium , the sporozoites initially multiply asexually within which human organ before attacking the red blood cells? Liver Spleen Pancreas Lymph nodes The formula for exponential population growth is- dt/dN = rN dN/rN = dt rN/dN = dt dN/dt = rN Which of the following organisms are responsible for causing pneumonia in humans by infecting the alveoli of the lungs? Streptococcus pneumoniae and Haemophilus influenzae Salmonella typhi and Wuchereria bancrofti Rhinoviruses and Plasmodium vivax Entamoeba histolytica and Escherichia coli The fungal genera Microsporum, Trichophyton, and Epidermophyton are primarily responsible for which condition in humans? Ringworm Amoebiasis Filariasis Ascariasis The 'Physiological barriers' of innate immunity include which of the following? Acid in the stomach, saliva in the mouth, and tears from eyes Skin and mucus coating of the respiratory tract Natural killer cells and monocytes Interferons produced by virus-infected cells The primitive prokaryotes responsible for the production of biogas from the dung of ruminant animals include the: Methanogens Eubacteria Halophiles Thermoacidophiles Cell-mediated immunity (CMI) is primarily mediated by which type of cells? T-lymphocytes B-lymphocytes Thrombocytes Erythrocytes The use of anti-histamines and steroids is a common treatment for which condition? Allergy Typhoid Malaria Ringworm Which of the following is considered the 'Main Lymphoid Organ' where all blood cells including lymphocytes are produced? Bone marrow Thymus Spleen Tonsils The inflorescences, leaves, and resin of the plant Cannabis sativa are used to produce which group of drugs? Cannabinoids Opioids Coca alkaloids Barbiturates During the production of curd from milk, Lactic Acid Bacteria (LAB) produce acids that: Coagulate and partially digest the milk proteins Increase the fat content of the milk Convert lactose into citric acid Destroy the Vitamin B 12 present in milk In a sewage treatment plant (STP), the 'primary treatment' step involves the removal of: Large and small particles through filtration and sedimentation Dissolved organic matter through microbial action Toxic chemicals using chlorine Pathogenic bacteria using UV radiation Niche overlap indicates- Active cooperation between two species Two different parasites on the same host Sharing of one or more resources between the two species Mutualism between two species Which of the following cyanobacteria can fix atmospheric nitrogen and serve as important biofertilizers in paddy fields? Anabaena and Nostoc Rhizobium and Azotobacter Lactobacillus and Streptococcus Methanobacterium and Trichoderma A person has lost a lot of blood and is given an injection of 'Antitoxin' against Tetanus. This is an example of: Passive Immunisation Active Immunisation Autoimmunity Innate Immunity During an allergic reaction, the release of which chemicals from mast cells causes symptoms like sneezing and watery eyes? Histamine and Serotonin Adrenaline and Cortisol Insulin and Glucagon Dopamine and Acetylcholine In the human stomach, besides converting milk to curd, Lactic Acid Bacteria (LAB) also play a beneficial role by: Checking the growth of disease-causing microbes Increasing the acidity of the stomach to kill all bacteria Producing proteases for protein digestion Synthesizing large amounts of Vitamin C The vector responsible for the transmission of both Dengue and Chikungunya is: Aedes aegypti Anopheles stephensi Culex pipiens Glossina palpalis In a biogas plant, the 'floating cover' placed over the slurry serves the purpose of: Rising as gas is produced in the tank Allowing aerobic bacteria to enter the slurry Keeping the temperature of the slurry constant Preventing the escape of CO 2 while allowing CH 4 to pass The progressive decrease in the number of which cells during HIV infection leads to the person becoming immunocompromised? Helper T-lymphocytes B-lymphocytes Natural Killer cells Platelets Smoking is known to increase the concentration of which gas in the blood, leading to a deficiency of oxygen in the body? Carbon monoxide ( CO ) Carbon dioxide ( CO 2 ) Nitrogen oxide ( NO ) Sulfur dioxide ( SO 2 ) Cocaine, also known as 'coke' or 'crack', acts as a potent stimulant because it interferes with the transport of the neurotransmitter: Dopamine Acetylcholine GABA Glutamate Methanogens are found in the rumen of cattle where they help in the breakdown of and play an important role in the nutrition of cattle. Cellulose Proteins Lipids Glycogen Which one of the following is the most suitable medium for culture of Drosophila melanogaster ? Moist bread Agar-agar Ripe banana cow dung Alexander Fleming discovered the first antibiotic while working on which of the following bacterial cultures? Staphylococci Streptococci Pneumococci Salmonella Which of the following pairs of fermented beverages are produced without distillation? Wine and Beer Whiskey and Brandy Rum and Gin Vodka and Fenny The vitamin whose content increases following the conversion of milk into curd by Lactic Acid Bacteria is: Vitamin B 12 Vitamin C Vitamin D Vitamin E The Ganga Action Plan and Yamuna Action Plan were initiated by the: Ministry of Environment and Forests Ministry of Agriculture and Farmers Welfare Ministry of Health and Family Welfare Ministry of Jal Shakti Heroin is a drug that belongs to the category of opioids and its primary physiological effect is that it: Acts as a depressant and slows down body functions Is a stimulant that increases energy and alertness Causes intense hallucinations and altered perception Directly stimulates the release of insulin In a severe case of Typhoid, which of the following complications is most likely to occur? Intestinal perforation Alveolar blockage with fluid Blockage of the intestinal passage by worms Inflammation of the lymphatic vessels The transmission of Ascaris lumbricoides occurs through the ingestion of water, vegetables, or fruits contaminated with which of the following? Eggs of the parasite Larvae of the parasite Adult worms Cysts of the protozoan The fungal infection 'Ringworm' is intensified by which of the following environmental factors? Heat and moisture Cold and dry weather High altitude UV radiation Which of the following is an example of an innate immunity barrier that involves the 'Mucus coating' of the epithelium? Physical barrier Physiological barrier Cellular barrier Cytokine barrier The time period between the initial infection of HIV and the appearance of AIDS symptoms can typically vary from: 5 to 10 years 2 to 4 weeks 1 to 2 months 15 to 20 years Geometric representation of age structure is a characteristic of population landscape ecosystem biotic community. Which chemical modification of morphine results in the production of 'Heroin'? Acetylation Methylation Glycosylation Nitration In a biogas plant, the 'slurry' consists of which of the following components? Dung mixed with water Concentrated methane gas Dried agricultural waste and ash Pure bacterial culture The use of 'Toddy', a traditional drink in Southern India, involves the fermentation of sap from which plant? Palms Coconut only Bamboo Sugarcane Which of the following is a symbiotic nitrogen fixer? Rhizobium Azotobacter Azospirillum Oscillatoria The 'floating cover' of a biogas plant moves in which direction as the gas is produced in the tank? Upward Downward Sideways It remains stationary Which of the following is used as an 'immunosuppressive agent' in organ-transplant patients to prevent graft rejection? Cyclosporin A Statins Streptokinase Penicillin Which of the following biofertilizers is particularly important in paddy (rice) fields? Cyanobacteria Mycorrhiza Rhizobium Glomus Match the following diseases with the causative organism and select the correct option: (a) Typhoid (b) Pneumonia (c) Filariasis (d) Malaria. (i) Wuchereria (ii) Plasmodium (iii) Salmonella (iv) Haemophilus. (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii) (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii) (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i) (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv) Which of the following immune responses is responsible for the rejection of a kidney graft? Cell-mediated immune response Auto-immune response Humoral immune response Inflammatory immune response What is the function of Statins? Blood cholesterol lowering agent Clot buster Immunosuppressant Digestion of fats A high density of elephant population in an area can result in intra specific competition inter specific competition predation on one another mutualism. During sewage treatment, biogas are produced which include: Methane, Hydrogen sulphide, Carbon dioxide Methane, Oxygen, Hydrogen sulphide Hydrogen sulphide, Methane, Sulphur dioxide Hydrogen sulphide, Nitrogen, Methane The first antibiotic to be discovered was: Penicillin Streptomycin Neomycin Tetracycline BOD (Biochemical Oxygen Demand) of waste water is estimated by measuring the amount of: Oxygen consumption Total organic matter Biodegradable organic matter Oxygen evolution A biocontrol agent used for controlling plant butterfly caterpillars is: Bacillus thuringiensis Trichoderma Baculoviruses Nostoc Baculoviruses (Nucleopolyhedrovirus) are excellent candidates for: Species-specific, narrow spectrum insecticidal applications Broad spectrum insecticidal applications Killing all useful insects in the ecosystem Increasing the population of pests Mycorrhiza does not help the host plant in: Increasing its resistance to insects Enhancing its phosphorus uptake capacity Increasing its tolerance to drought Enhancing its resistance to root-borne pathogens The sexual stages (gametocytes) of the malarial parasite Plasmodium develop in which of the following hosts? Human red blood cells Human liver cells Gut of female Anopheles mosquito Salivary glands of female Anopheles mosquito In pneumonia, the infection occurs in the whereas in common cold, it affects the . Alveoli; nose and respiratory passage Nose; alveoli and bronchi Lungs; entire digestive tract Bronchioles; only the throat What is the primary mechanism by which 'Contact Inhibition' prevents normal cells from becoming cancerous? Normal cells stop growing when they come into contact with other cells Normal cells undergo programmed cell death when crowded Normal cells secrete toxins to kill neighboring cells Normal cells double their DNA content to outcompete others Which of the following is an example of a physiological barrier of innate immunity? Acid in the stomach Polymorpho-nuclear leukocytes (PMNL) Monocytes Skin