General Science Questions (MCQs) for Competitive Examinations

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Down syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is typically associated with physical growth delays, characteristic facial features and mild to moderate intellectual disability.

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Rhizobia are soil bacteria that fix nitrogen after becoming established inside root nodules of legumes. They are the only nitrogen-fixing bacteria living in a symbiotic relationship with legumes. Common crop and forage legumes are peas, beans, clover, and soy.

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The process of photosynthesis occurs when green plants use the energy of light to convert carbon dioxide (CO2) and water (H2O) into carbohydrates. Light energy is absorbed by chlorophyll, a photosynthetic pigment of the plant, while air containing carbon dioxide and oxygen enters the plant through the leaf stomata.

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Vegetable and fruits should be a part of our diet because they stimulate peristalsis. Dietary fiber found in whole fresh fruits and vegetables and whole grains stimulates peristalsis, flushing out fats and waste. Gas-producing foods like broccoli and cabbage also stimulate peristalsis. Drinking plenty of fluids is important because it keeps stools soft and easy to pass.

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The foramen magnum (“great hole”) is a large opening in the occipital bone of the cranium. It is one of the circular apertures in the base of the skull (the foramina), through which the spinal cord (an extension of the medulla oblongata) enters and exits the skull vault.

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Eutrophication is the ecosystem response to the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage. It leads not only to increased levels of nutrients, but increased Biological Oxygen Demand as well following the decay of algal bloom in stagnant water reservoirs.

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Bonsai is the art of aesthetic miniaturization of trees and plants in containers. A bonsai plant is not a dwarf plant but equal to the full sized flowering plant. The main objective of bonsai plants is to create a tree or plant, and even landscapes, in miniature at household level.

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In algae, sexual reproduction takes place through fusion of two gametes. It is of two types on the basis of the size of gametes : isogamous (where male and female gametes are morphologically similar) and heterogamous (anisogamous and oogamous). Anisogamous fusion happens when gametes are dissimilar in size.

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Those who eat a well-balanced diet and have no metabolic disorders, excess dietary carbohydrates?are converted by the liver into complex chains of glucose called glycogen. Glycogen is stored in liver and muscle cells and is a secondary source of energy to freely circulating blood glucose.

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Sarpagandha plant is used to treat blood pressure. It’s one of the major source of resperine. The powder derived from Sarpagandha roots is an excellent natural remedy for treating hypertension. Sarpagandha lowers blood pressure and improves blood circulation by dilating the blood vessels and controlling nerve function in the muscles that lead to the heart.