Biology [2 Mark Question Answer]

The role of insulin in maintaining blood sugar level is that it lowers blood glucose level and induces protein synthesis. Insulin also initiates deposition of extra glucose in the liver and muscles as glycogen.

Mouth dries up and heartbeat increases during public speaking. It is due to adrenaline hormone which prepares the body to meet any emergency situation. It makes the heartbeat faster. At the same time, it stimulates constriction of arterioles of the digestive system reducing the blood supply of the digestive system which makes the mouth dry.

Yes. Hormones are transmitted chemically through blood. They can bring about specific chemical changes and regulate metabolism. They activate each other and work in a coordinated manner. As for example, the hormone insulin acts on liver and muscle cells and deposit extra glucose in the form of glycogen.

The hormone responsible for this is adrenaline. It is a hormone, which prepares the body to meet any emergency situation, for "Fight" i.e. to face danger or for "flight", i.e. to run away from it. Extra hormone is released into the blood at the time of emotional stress.

Iodine is the active ingredient in the production of thyroxine and thyroxine, in turn promotes tissue metabolism, growth and differentiation. Thus, it is important for our body.

Adrenaline is a hormone which prepares the body to meet any emergency situation to 'fight', i.e., to face the danger or for 'flight', to run away from it, and extra energy and strength are provided to the body for the situation. Extra hormone is released into the blood at the time of emotional stress. The gland itself is stimulated by the nerve endings of the autonomic nervous system.

The pituitary gland is referred to as the 'master gland', because the activities and growth of the endocrine glands and somatic cells are under the influence of secretions of the pituitary gland. Nearly 50,000 nerve fibres enter this fragment of tissue, and an enormously rich blood supply carries its hormones to the rest of the body.

The thyroid gland regulates the body metabolism, including causing an increase in basal metabolic rate which raises the body temperature. With advancing age, the activity of thyroid gland slows down and body heat production is lowered. That is why, older people tend to feel colder than youngsters.

Male sex hormone stimulates the development of external male characters. It also promotes the growth of many parts of the body tissues, including bones and muscles. Since females do not have these hormones (androgens), they do not grow as tall and or have strong stature.

People in the hilly region usually develop goitre because of the enlargement of thyroid gland. Deficiency of iodine in diet causes the thyroid to enlarge to produce inadequate amount of thyroxine.

The sex hormones are secreted by the gonads. In males, the hormones secreted are testosterone and androgen. They are responsible for:
(a) normal maturation of sperms,
(b) stimulation of secondary sex characters i.e. facial hair (beard), pattern of body hair, low pitch of voice
(c) broadening of shoulders,
(d) influence sex instinct and reflexes. In females, the hormone oestrogen stimulates the development of secondary sexual characterstics at puberty, i.e., development of hair in pubic region and in the armpits, development of breast, fat deposits in hips and high pitch of voice.

The cause of the development of beard in females and breasts in males with normal karyotype is due to excessive secretion of sex corticoids.

Hormones - Hormones are the organic chemical messengers that they bring about various changes in the body. Hormones generally do not act independently. They work together with other hormones and also with the nervous system. Hormones are secreted by various glands such as pancreas, thyroid, pituitary, etc.

Tropic hormone - Tropic hormones are the hormones that control the release of other hormones. These hormones travel through the blood to the target gland and cause the cells of that gland to start releasing hormone. Most tropic hormones are produced and secreted by the anterior pituitary. Use of tropic hormones allows for rapid hormone control, amplification of original signal and control of hormone released by the brain.

Diabetes insipidus - It is defined as the condition in a person that occurs due to the deficiency of ADH (Antidiuretic hormone). It leads to frequent and copious urination causing excessive thirst.