Differentiate between endocrine and exocrine glands. Describe the function of pituitary gland.

Differentiation between Endocrine and Exocrine Glands:

Endocrine Glands:

1. Secretion Method:

   • Endocrine glands release hormones directly into the bloodstream, allowing these chemical messengers to travel to distant target organs and tissues.

2. Ducts:

   • Endocrine glands lack ducts. Instead of transporting their secretions through ducts, hormones are released directly into the bloodstream.

3. Mode of Action:

   • Hormones produced by endocrine glands act as signaling molecules, affecting target cells and tissues throughout the body. The effects are often widespread and systemic.

4. Examples:

   • Examples of endocrine glands include the pituitary gland, thyroid gland, adrenal glands, and pancreas.

Exocrine Glands:

1. Secretion Method:

   • Exocrine glands secrete their products through ducts onto an epithelial surface, typically a body cavity or the outer surface of the skin.

2. Ducts:

   • Exocrine glands have ducts that transport their secretions to a specific location or surface.

3. Mode of Action:

   • The secretions of exocrine glands play roles in digestion, lubrication, and protection. They act locally rather than exerting systemic effects.

4. Examples:

   • Examples of exocrine glands include salivary glands, sweat glands, sebaceous glands, and digestive glands like the pancreas.

Function of the Pituitary Gland:

The pituitary gland, often referred to as the "master gland," is a pea-sized gland located at the base of the brain in a small bony cavity called the sella turcica. It consists of two lobes – the anterior pituitary (adenohypophysis) and the posterior pituitary (neurohypophysis), each with distinct functions.

1. Anterior Pituitary (Adenohypophysis):

   • The anterior pituitary produces and releases several hormones that regulate various physiological processes:
     • Growth Hormone (GH): Stimulates growth, cell reproduction, and regeneration.
     • Thyroid-Stimulating Hormone (TSH): Stimulates the thyroid gland to produce and release thyroid hormones.
     • Adrenocorticotropic Hormone (ACTH): Stimulates the adrenal glands to produce cortisol, involved in stress response.
     • Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH): Regulate the reproductive system, influencing the development of eggs and sperm, as well as the production of sex hormones (estrogen and testosterone).
     • Prolactin (PRL): Stimulates milk production in the mammary glands.

2. Posterior Pituitary (Neurohypophysis):

   • The posterior pituitary stores and releases hormones produced by the hypothalamus, which include:
     • Oxytocin: Regulates uterine contractions during childbirth and stimulates milk ejection during breastfeeding. Also involved in social bonding and emotional responses.
     • Vasopressin (Antidiuretic Hormone – ADH): Regulates water balance by influencing the reabsorption of water in the kidneys. Plays a role in maintaining blood pressure.

The pituitary gland's function is tightly regulated by the hypothalamus, a region of the brain that releases hormones controlling the pituitary's hormone secretion. The intricate interplay between the hypothalamus and pituitary is crucial for maintaining hormonal balance and regulating various physiological processes throughout the body.