Question

Given below is an outline of the human body showing the important glands.

(i) Name the glands marked 1 to 5.
(ii) Name the hormone secreted by 2. Give one important function of this hormone.
(iii) Name the endocrine cells present in part 3.
(iv) Name the hormone secreted by part 4. Give one important function of this hormone.

Answer 1

(i) Labelling of glands

Label 1- Pituitary gland

1. The pituitary gland also called the master endocrine gland, is attached to the hypothalamus at the base of the brain.
2. It secretes tropic hormones that control the functioning of other glands.

Label 2- Thyroid gland

1. The thyroid gland is situated in the front of the neck region above the trachea and below the larynx.
2. It secretes hormones that control the metabolism of the body.

Label 3 - Pancreas

1. The pancreas is a leaf-shaped gland located in the abdominal region slightly inferior and posterior to the stomach.
2. It is a heterocrine gland that performs exocrine (secrete pancreatic juice) and endocrine (secrete insulin and glucagon) functions.

Label 4 - Adrenal gland

1. The adrenal glands are double glands present above each kidney. They appear yellowish and are divided into an outer cortex and an inner medulla.
2. The cortex secretes corticosteroids whereas the medulla secretes adrenaline and noradrenaline.

Label 5 - Ovaries

1. The ovaries are a pair of oval organs that are situated in the pelvic region of females.
2. They secrete estrogen and progesterone that regulate various aspects of the female reproductive system.

Labelling the image-

(ii) The hormone secreted by the thyroid gland

1. Part 2 is the thyroid gland. The thyroid gland is located on the front side of the neck above the trachea and below the larynx.
2. The thyroid gland is bilobed and butterfly-shaped.
3. The thyroid gland secretes thyroxine and calcitonin.

The function of thyroxine

1. Thyroxine hormone helps in controlling the basal metabolic rate (BMR) and temperature of the body.

(iii) Cells of the endocrine part of the pancreas:

1. Part 3 is the pancreas.
2. The pancreas is a heterocrine gland that performs exocrine (secrete pancreatic juice) and endocrine (secrete insulin and glucagon) functions.
3. The endocrine function in the pancreas is performed by the islets of Langerhans which are present as small patches
4. Islets of Langerhans are made up of alpha, beta, and delta cells that secrete glucagon, insulin, and somatostatin respectively.

(iv) The hormones released by adrenal glands

1. Part 4 is the adrenal gland.
2. The adrenal glands are double glands present above each kidney. They appear yellowish and are divided into an outer cortex and an inner medulla.
3. The cortex secretes three types of corticosteroids- mineralocorticoids, glucocorticoids, and sex corticoids.
4. The adrenal medulla secretes adrenaline and noradrenaline.

Functions:

1. The mineralocorticoids help in maintaining the water and electrolyte balance of the body, glucocorticoids regulate carbohydrate metabolism, and gonadocorticoids regulate the development of external sex characters.
2. These act as the emergency hormone and prepare the body for flight and fight response.