Biology MCQs

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Genetic variability is usually due to a mutation during meiosis (sexual reproduction). In the above question, the answer choices (B) and (D) are examples of asexual reproduction. They create identical offspring.

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Guard cells are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata. Guard cells are specialized cells in the epidermis of leaves, stems and other organs that are used to control gas exchange. They are produced in pairs with a gap between them that forms a stomatal pore.

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The discovery in 1953 of the double helix, the twisted-ladder structure of deoxyribonucleic acid (DNA), by James Watson and Francis Crick marked a milestone in the history of science and gave rise to modern molecular biology, which is largely concerned with understanding how genes control the chemical processes.

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The chemical name of Vitamin B3 is Niacin which is a water soluble vitamin. It is an important nutrient. In fact, every part of your body needs it to function properly. As a supplement, niacin may help lower cholesterol, ease arthritis and boost brain function, among other benefits.

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A specific epithet is the second part of a species name in binomial nomenclature in any branch of biology. In botany, the second part of a botanical name. Specific epithet (zoology), also called the specific name, meaning the second part of the species name or binomen.

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Oxygen is a natural element which no animal can live without. Fish and other aquatic animals depend on oxygen gas dissolved in water as much as people depend on oxygen gas in air. Many people are surprised to learn that fish and other aquatic organisms don’t use oxygen from water molecules (H2O). This is because the single oxygen molecule (O) is bound to the two hydrogen molecules (H2) and is not useable in this form. Instead, aquatic organisms depend on dissolved oxygen gas (O2), a colorless, tasteless and odorless substance that enters the water from plants and the atmosphere.

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Genetics is the study of heredity in general and genes in particular. Genetics is one of the central pillars of biology and overlaps with many other fields such as agriculture, medicine and biotechnology.

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Schwann discovered the enzyme pepsin and discovered glial cells in nerves – these are now known as Schwann cells. He also identified the role of microorganisms in alcohol fermentation.

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Rudolf Virchow was a German pathologist and politician who pioneered the modern concept of disease processes by his application of cell theory to explain the effects of disease in body organs and tissues.

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Endocytosis is the process in which the ingestion of material by the cells is carried out through the plasma membrane.