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Chemical Coordination and Integration

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Biology

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Biology

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12

Explain the following :

(1) Insulin lowers the blood sugar level.

(2) Adrenal medulla and the sympathetic nervous system function as a closely integrated system.

(3) Pituitary gland regulates the reproductive system.

(4) Feed back system controls the blood level of many hormones.


(1) Insulin is reponsible for lowering the blood sugar level by converting excess of glucose to gylcogen which is stored in muscles and liver. 

(2) Adrenal medulla and the sympathetic nervous system are closely integrated systems as noradrenaline is secreted during danger when nerve impulse reaches adrenal medulla via the sympathetic nerves.

(3) Gonadotrophic hormone secreted by pituitary gland controls spermatogenesis in male and ovulation of mature follicles , growth and development of ovarian follicles and maintenance of corpur luteum in females. 

(4) Hormones maintain homeostasis. Hormones produced in body are under the control of hormones secreted by pituitary gland and hormones of pituitary gland are further controlled by hormones of hypothalamus. All this control of hormones is done by feed back mechanism. For example, if thyroxin amount is more in blood then it stimulates hypothalamus to secrete less thyrotropin releasing hormones which decreases thyroxine secretion. On decrease in amount of thyroxine below normal, thyrotrophin releasing hormone accelerates the release of thyroxine secretion. This is feed back control.

181 Views

What is goitre?

Goitre is the condition in the the thyroid gland is enlarged and the neck portion becomes swollen .It is due to the deficiency of iodine in our diet which results in the less production and secretion of the thyroid hormones that is hypothyroidism.
467 Views

Why is the Parathyroid hormone called hypercalcemic hormone?

PTH or parathyroid hormone is also called hypercalcemic hormone as it increase the calcium level in the blood.
585 Views

Name the endocrine gland which is H shaped.

Thyroid gland.
813 Views

Name the largest endocrine gland.

Thyroid gland.
479 Views

Name the cells that the thyroid gland is composed of.

The thyroid gland is composed of the following :
i. Follicles
ii. Stromal tissue
523 Views