Describe the parathyroid gland and adrenal gland in detail.

The parathyroid gland is a small, pea-sized gland located in the neck, usually situated behind the thyroid gland. Most people have four parathyroid glands, but some individuals may have more. The main function of the parathyroid gland is to regulate the levels of calcium in the blood. It does this by producing parathyroid hormone (PTH), which helps to increase calcium levels in the blood by stimulating the release of calcium from the bones and increasing the absorption of calcium from the intestines.

The adrenal glands are two small, triangular-shaped glands located on top of each kidney. Each adrenal gland is divided into two parts: the outer adrenal cortex and the inner adrenal medulla. The adrenal glands play a crucial role in the body's response to stress and help regulate metabolism, immune function, blood pressure, and other essential functions.

The adrenal cortex produces hormones such as cortisol, aldosterone, and sex hormones. Cortisol helps the body respond to stress and regulate metabolism, while aldosterone helps regulate blood pressure and electrolyte balance. The adrenal medulla produces hormones such as adrenaline and noradrenaline, which are involved in the body's fight-or-flight response to stress.

Overall, both the parathyroid gland and adrenal gland play important roles in maintaining the body's overall health and functioning.

Parathyroid Glands

- Anatomy:
- Small, round, oval glands located on the posterior surface of the thyroid gland
- Usually 4 in number: 2 superior and 2 inferior parathyroid glands
- Parathyroid glands are embedded in the thyroid but have their own capsule
- Function:
- Secrete parathyroid hormone (PTH), which regulates calcium metabolism
- PTH increases blood calcium levels by:
- Stimulating the release of calcium from bone
- Increasing calcium reabsorption in the kidneys
- Decreasing calcium excretion in the urine
- Regulation of PTH secretion:
- Regulated by the blood calcium level
- Low blood calcium levels stimulate PTH secretion
- High blood calcium levels inhibit PTH secretion

Adrenal Glands

- Anatomy:
- Triangular-shaped glands located on top of each kidney
- Consists of two distinct regions:
- Adrenal cortex: Outer layer
- Adrenal medulla: Inner layer
- Adrenal Cortex:
- Function: Secrete steroid hormones called glucocorticoids and mineralocorticoids
- Glucocorticoids:
- Cortisol is the primary glucocorticoid
- Regulates metabolism, stress response, and immune function
- Mineralocorticoids:
- Aldosterone is the primary mineralocorticoid
- Regulates electrolyte balance, particularly sodium and potassium
- Adrenal Medulla:
- Function: Secrete catecholamines, including adrenaline (epinephrine) and noradrenaline (norepinephrine)
- Catecholamines:
- Prepare the body for the "fight or flight" response
- Increase heart rate, blood pressure, and respiration
- Regulation of Adrenal Gland Activity:
- Adrenal cortex is regulated by the pituitary hormone adrenocorticotropic hormone (ACTH)
- Adrenal medulla is regulated by the sympathetic nervous system

Describe social changes affecting health