General Science Questions (MCQs) for Competitive Examinations

Notes:
Keratin is a family of fibrous structural proteins involved in making up the outer layer of human skin. It is also the key structural component of hair and nails. Cells in the epidermis contain a structural matrix of keratin, which makes this outermost layer of the skin almost waterproof, and along with collagen and elastin, gives skin its strength. It also makes up fish scales and crustacean shells, bird feathers and beaks, animal horns and hooves.

Notes:
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.

Notes:
Coriander (Coriandrum sativum), also known as cilantro, Chinese parsley or dhania, is an annual herb in the family Apiaceae. All parts of the plant are edible, but the fresh leaves and the dried seeds are the parts most traditionally used in cooking.

Notes:
Pituitary gland, called Master Gland, is the smallest endocrine gland. It controls the general growth of the body coordinating the functioning of other endo crime glands and stimulates the primary sex hormones, i.e. ovaries and testes.

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The thyroid gland is one of the largest endocrine glands in the human body which is found in the neck. It controls how quickly the body uses energy, makes proteins, and controls how sensitive the body is to other hormones.

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Plant wilting occurs after excessive loss of water by transpiration and lesser absorption. i.e. rate of transpiration exceeds rate of water absorption. On a hot day, plants transpire heavily and cannot absorb water speedily to keep pace with transpiration loss, even when there is enough water.

Notes:
Infection is the invasion of an organism’s body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce. Infectious diseases can be spread from one person to another, for example through contact with bodily fluids, by aerosols (through coughing and sneezing), or via a vector, for example a mosquito.

Notes:
It is assumed that protodermal cells divide periclinally in certain cases to form multiseriate or multiple epidermis. The multiple epidermis is found in some organs like roots of orchids (Vanda), leaves of Ficus, Nerium, Piperomia, etc. In Nerium, it is found on both surfaces.

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There are several hormones in females which are naturally produced and secreted by the glands of the endocrine system. Among them, estrogen, and progesterone are secreted for the influence on a woman’s reproductive health and are termed as female sex hormones. Estrogen and progesterone are made by the ovaries.

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The masseter is located in the jaw and is one of the muscles of mastication or chewing. ? The bite strength of an average man is between 117 to 265 pounds. ? This ability to exert a force on an external object is an example of absolute strength.