THYROXINE, INSULIN, ADRENALIN AND GROWTH HORMONE

THYROXINE, INSULIN, ADRENALIN AND GROWTH HORMONE

Look at Fig. 10.3 again.

Figure 10.3: The onset of puberty is controlled by hormones

The hormones secreted by the pituitary stimulate testes and ovaries to produce their hormones. You have already learnt that the pituitary gland is an endocrine gland. It is attached to the brain.

Apart from the pituitary, the testes and the ovaries, there are other endocrine glands in the body such as thyroid, pancreas and adrenals (Fig. 10.5).

Figure 10.5: Position of endocrine glands in the human body

Boojho and Paheli had once visited their aunt who was a doctor and remembered that a boy named Kaka had a very big and bulging throat. Their aunt had told them that Kaka was suffering from ‘goitre’, a disease of the thyroid gland. Kaka’s thyroid gland was not producing the hormone thyroxine.

Their aunt also told them that their uncle was suffering from ‘diabetes’ because his pancreas was not producing the hormone insulin in sufficient quantities. Boojho and Paheli then asked their aunt about the adrenal glands, which are also shown in the chart hung on the wall of her clinic. The aunt told them that adrenal glands secrete hormones which maintain the correct salt balance in the blood. Adrenals also produce the hormone adrenalin. It helps the body to adjust to stress when one is very angry, embarrassed or worried.

Thyroid and adrenals secrete their hormones when they receive orders from the pituitary through its hormones. Pituitary also secretes growth hormone which is necessary for the normal growth of a person.

Questions

Are there hormones in other animals also? Have they any role to play in reproduction?

Source: This topic is taken from NCERT TEXTBOOK