Biology MCQs

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Innate immunity is the defense system you are born with. It protects against all antigens. Innate immunity involves barriers that prevent harmful substances from entering the body.

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The pancreas secretes digestive enzymes into the duodenum that break down proteins, fats, and carbohydrates.

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Cowpox diseases can be transmitted to humans during milking. Cowpox is an infectious disease caused by the cowpox virus.

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Sesbania is green manure. Sesbania is a leguminous crop. It is commonly used as a green manure crop to add nitrogen and organic matter to the soil.

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Anabaena is the nitrogen-fixing symbiotic organism present in Azolla. Anabaena is a genus of filamentous cyanobacteria that exist as plankton.

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Vitamin C (Ascorbic acid) cures scurvy, which can cause abnormal gum bleeding. Excellent sources include citrus fruits such as oranges, lemons, limes, and grapefruits. Researchers examined 15 published studies involving 1,140 healthy people as well as data on 8,210 people from the CDC’s Health and Nutrition Examination Survey. They found that low vitamin C levels in the bloodstream were associated with an increased risk for gum bleeding with gentle probing.

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Chitin is the main component of the cell walls of fungi, the exoskeletons of arthropods such as crustaceans (e.g., crabs, lobsters and shrimps) and insects, the radulas of molluscs, and the beaks and internal shells of cephalopods, including squid and octopuses. Combined with calcium carbonate, as in the shells of Crustacean and molluscs, chitin produces a much stronger composite for protection.

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The best-known and most common chromosome abnormality in humans is Down’s syndrome, (Trisomy of 21st pair of chromosome). Down’s syndrome individuals also almost invariably develop Alzheimer’s disease, a form of dementia that is fairly common among the elderly people. People with Down’s syndrome develop this disease in their fourth or fifth decade of life, much sooner than other people. These people are also characterized by presence of webbed neck, Plamers crease, very broad forehead, round face and forked tongue.

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Cotton is the most popular of the BT crops. In BT cotton, BT gene was isolated and transferred from a bacterium Bacillus thurigiensis to American cotton. The American cotton was subsequently crossed with Indian cotton to introduce the gene into native varieties. The BT cotton variety contains a foreign gene obtained from Bacillus thuringiensis. This bacterial gene, introduced genetically into the cotton seeds, protects the plants from bollworm (A. lepidoptora), a major pest of cotton.

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Riboflavin, also known as vitamin B2 is an easily absorbed colored micronutrient with a key role in energy metabolism, and for the metabolism of fats, ketone bodies, carbohydrates, and proteins.