Biology MCQs

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Rhizobium Found in roots of legumes, like Peas, grams, Pulses etc, where it fixes atmospheric nitrogen as ammonia, which is then converted into useful amino acid.

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Gymnosperms are called so because they have naked ovules / seeds. In terms of plant evolution, they are first seed-bearing plants. They are inferior to Angiosperms because in Angiosperms, the ovules are covered.

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Dengue which is found in tropical and subtropical regions around the world is a mosquito borne disease and caused by a virus. Symptoms typically begin to appear three to fourteen days after infection.

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Thrombin is a naturally occurring enzyme that converts fibrinogen into fibrin, which is an integral step in clot formation. Ca2+ is essential for both activation and action of thrombin.

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Carcinoma group represents the most commonly found cancers in the world. Carcinoma is a cancer which begins in a tissue that lines the inner or outer surfaces of the body, and that arises from cells originating in the endodermal, mesodermal or ectodermal germ layer during embryogenesis.

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Dr. Robert Koch was a German (Prussian) physician. In 1877 he isolated Bacillus anthracis (causative agent of Anthrax) . He also isolated Tuberculosis bacillus (Causative agent of TB) and Vibrio cholera (causative agent of Cholera). He is also known to develop Koch’s postulates, the four criteria designed to establish a causal relationship between a causative microbe and a disease. He was awarded the Nobel Prize in Physiology or Medicine for his tuberculosis findings in 1905.

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A tablet of Vitamin C should be advised to be used after purification of water by Iodine as a disinfectant. The addition of vitamin C usually in the form of a pill or in flavored drink powders, precipitates much of the iodine out of the solution.

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A pigment called luciferin is found in firefly. Luciferin is a light-emitting compound which is found in organisms that generate bioluminescence. Luciferins typically undergo an enzyme-catalyzed reaction with molecular oxygen.

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Dermatogen is the outer primary meristem of a plant or plant part that according to the histogen theory gives rise to epidermis, which is the outermost layer of the skin. Epidermis provides barrier to infection from environmental pathogens.

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Mitochondria is known as the Powerhouse of the Cell as it plays host to one of the most important processes in your body: cellular respiration. Taking in glucose and oxygen, mitochondria produce energy, which they capture and package as energy-rich molecules of ATP.