### Theory:

As we have seen in previous theories, testosterone is the hormone secreted by the endocrine gland testes.

At the same time, estrogen is the hormone that is secreted by the endocrine gland ovaries. The pituitary gland is also an endocrine gland attached to the brain that secretes hormones that stimulate the ovary and testis to produce sex hormones.

There is the presence of hormones other than sex hormones. Apart from the pituitary gland, other endocrine glands present are the thyroid, adrenal, pineal, and adrenals.

Endocrine glands
Pituitary gland
It is an endocrine gland attached at the base of the brain, which is about the size of a pea. The pituitary gland is present inside the skull and is called the master gland as it monitors and regulates the functions of other glands.
It secretes the growth hormone that controls the growth of an individual. It also secretes prolactin that stimulates the production of milk.

Pituitary gland
Thyroid gland
It is an endocrine gland that is present at the front of the neck. It is attached to the trachea and secretes thyroid hormones - triiodothyronine ($$T3$$) and thyroxine hormone ($$T4$$).
Thyroid hormones are secreted when the pituitary gland releases hormones. The thyroid hormone controls the rate of body metabolism. Iodine is required for the production of $$T4$$.
A deficiency of iodine in the diet may cause a deficiency in T4 productionLack of T4 hormone results in goitre, a disease of the thyroid gland. Goitre causes a swollen and bulging neck.

Iodised salt provides the needed iodine for the thyroid gland to secrete the $$T4$$ hormone.

Thyroid gland
Pancreas:
The pancreas is present behind the stomach and secretes the hormone insulin.
Insulin maintains and controls blood glucose levels. The deficiency of insulin in the body causes a disease called diabetes. Pancreas also secrete a hormone called glucagon. Glucagon prevents the insulin level from getting too low in the body.

Pancreatic gland