Biology MCQs

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Placenta found in humans is called discoidal. It is a placenta in which the chorionic villi are arranged in a circular plate.

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Whooping cough is caused by Bordetella pertussis causative agent. It is a Gram-negative, aerobic, pathogenic, and encapsulated coccobacillus of the genus Bordetella.

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Ovine campylobacteriosis is an infectious disease that causes miscarriage in late pregnancy. It is caused by the bacteria Campylobacter fetus.

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The Gene of DNA provides information for one protein. This is the basic physical and functional unit of heredity.

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Sesbania rostrata legumes have a symbiotic relationship with two nitrogen-fixing bacteria.

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A molecule that contains nitrogen and has the chemical properties of a base is called a Nitrogenous base. Nucleic acids are composed of a combination of 5 nitrogenous bases:
1. Guanine and adenine are double-ringed purine molecules.
2. Cytosine, thymine, and uracil are single-ringed pyrimidine molecules.

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There are basically two approaches to cloning the entire genome. In the first approach, systematic cloning is performed and the second approach is based on randomly cloning overlapping fragments.

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Insulin is central to regulating carbohydrate and fat metabolism in the body. It stops the use of fat as an energy source by inhibiting the release of glucagon. It removes excess glucose from the blood, which otherwise would be toxic. Insulin helps blood sugar enter the body’s cells so it can be used for energy. Insulin also signals the liver to store blood sugar for later use. Blood sugar enters cells, and levels in the bloodstream decrease, signaling insulin to decrease too.

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Echo location, also called biosonar, is the biological sonar used by several kinds of animals. Echo-locating animals emit calls out to the environment and listen to the echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects. Echo-locating animals include some mammals and a few birds; most notably microchiropteran bats and odontocetes (toothed whales and dolphins).

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Trans fat, also called trans-unsaturated fatty acids or trans fatty acids, is a type of unsaturated fat that occurs in small amounts in meat and milk fat. It became widely produced as an unintentional by product in the industrial processing. The World Health Organization (WHO) has launched a comprehensive plan to eliminate industrially-produced artificial trans fats from the global food supply by 2023. Unlike other dietary fats, trans fat also called transfatty acids both raises your LDL (“bad”) cholesterol and lowers your HDL (“good”) cholesterol. A diet laden with trans fat increases your risk of heart disease, the leading killer of men and women.