General Science Questions (MCQs) for Competitive Examinations

Notes:
The major proteins in milk are casein and whey. These two milk proteins are both excellent sources of all the essential amino acids, but they differ in one important aspect—whey is a fast-digesting protein and casein is a slow-digesting protein. As a food source, casein supplies amino acids, carbohydrates, and the two inorganic elements calcium and phosphorus.

Notes:
Both polio and chicken pox are caused by virus. Poliomyelitis, often called polio or infantile paralysis, is an infectious disease caused by the poliovirus; while, Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus (VZV).

Notes:
Cockroach and prawns have open circulatory system in which the blood is not confined within blood vessels. The blood bathes the organs and tissues directly. Open circulatory systems pump blood into a hemocoel with the blood diffusing back to the circulatory system between cells. Blood is pumped by a heart into the body cavities, where tissues are surrounded by the blood. The open circulatory system is common to molluscs and arthropods.

Notes:
Bacteria are the most abundant organisms which play important role in the decomposition of organic matter. Majority of bacteria involved in decomposition of organic matter are heterotrophs and autotrophs are least in proportion which are not directly involved in organic matter decomposition.

Notes:
The mottling of dental enamel is an extremely common disorder, characterized by hypomineralization of tooth enamel caused by ingestion of excessive fluoride during enamel formation. It is also known as dental fluorosis. Common causes of fluorosis include: fluoridated drinking water (particularly during infancy), ingestion of fluoride toothpaste, use of fluoride tablets, and consumption of processed foods made with fluoridated water.

Notes:
Black soil is most suitable for the cultivation of cotton. The deep and medium black lava soil of the Deccan and Malwa plateaus is considered ideal, though it can be grown on alluvial and red soil as well. The black cotton soil is also known as regur.

Notes:
The wings are modified forelimbs of birds which are the key to bird flight. Each wing is composed of three limb bones, the humerus, ulna and radius. Wings are much bigger than our arms, but being made mostly of feathers and hollow bones makes them very light. Their shape uses the wind to make flying easier.

Notes:
Acidity and alkalinity are expressed on the pH scale, which ranges from 0 (strongly acidic) to 14 (strongly basic or alkaline). A pH of 7.0, in the middle of this scale, is neutral. Blood is normally slightly basic, with a normal pH range of 7.35 to 7.45.

Notes:
Guard cells interact physiologically and mechanically with subsidiary cells. Guard cells are those which have chloroplasts and control the opening of stomata. But, subsidiary cells are those which support the guard cells and they do not have chloroplasts.

Notes:
Hermaphroditism is a form of sexual reproduction. Hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes. Hermaphroditic plants—most flowering plants, or angiosperms—are bisexual. Hermaphroditic animals—mostly invertebrates such as worms, moss animals, trematodes, snails, slugs etc are usually parasitic, permanently attached to another animal or plant.