Biology MCQs

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A genotype is a collection of genes of an individual. The term can also refer to two alleles inherited for a particular gene. The genotype is expressed when the information encoded in the gene’s DNA is used to make proteins and RNA molecules.

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The technique of genetic engineering crosses the limits of conventional hybridization processes.

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The Bacillus Calmette–Guérin (BCG) vaccine is used to prevent tuberculosis (TB). The BCG vaccine is named after Dr Albert Calmette and Dr Camille Guerin, who developed the vaccine from a germ called Mycobacterium bovis, which is similar to TB. BCG is a live vaccine that has been processed so that it is not harmful to humans. Tuberculosis is an infectious disease caused by bacteria that affects the lungs, and sometimes other parts of the body.

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These types of mechanism have been termed seismonastic movements. The movement occurs when specific regions of cells lose turgor pressure, which is the force that is applied onto the cell wall by water within the cell vacuoles and other cell contents.

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Trypsin is an enzyme that helps us digest protein. In the small intestine, trypsin breaks down proteins, continuing the process of digestion that began in the stomach. It may also be referred to as a proteolytic enzyme, or proteinase. Trypsin is produced by the pancreas in an inactive form called trypsinogen. The trypsinogen enters the small intestine through the common bile duct and is converted to active trypsin.

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When a plant is placed under the fan, the speed of air is increased which leads to high rate of transpiration through the stomata. The increase in the rate of transpiration increases the water absorption also. As by keeping the plants under the fan, the transpiration process is boosted. Therefore, more amount of water and other minerals are absorbed by the plant roots from the soil.

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Most species of Euglena have photosynthesizing chloroplasts within the body of the cell, which enable them to feed by autotrophy (making energy-containing organic molecules from inorganic raw material through the use of an energy source such as sunlight), like plants. However, they can also take nourishment heterotrophically (making use of food that comes from other organisms in the form of fats, carbohydrates, and proteins), like animals. So Euglena have features of both animals and plants.

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Syrinx is the name for the vocal organ of birds. Located at the base of a bird’s trachea, it produces sounds without the vocal cords of mammals. The sound is produced by vibrations of some or all of the membrana tympaniformis (the walls of the syrinx) and the pessulus caused by air flowing through the syrinx.

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Hydra doesn’t have blood. It is a single-cellular animal. In the hydra, respiration is accomplished via diffusion of molecules of oxygen and carbon dioxide through the skin whereas earthworm, cockroach and octopus has blood.

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Triploblasty is a condition of the blastula in which there are three primary germ layers: the ectoderm, mesoderm, and endoderm. The germ layers form during gastrulation of the blastula. All “higher” and “intermediate animals” (from flat worms to humans), arise from a triploblastic ovum. Triploblastic organisms generally possess bilateral symmetry.