51. Glandular epithelium - endocrine type.

Definition

Endocrine glands are ductless glands that secrete their products, primarily hormones, directly into the bloodstream rather than through ducts

Structure

• Endocrine glands lose their connection to the original epithelial surface during development.

• They are ductless and are typically surrounded by a rich network of capillaries, which facilitates the direct release of hormones into the blood.

Function

• The primary function of endocrine glands is to secrete hormones (which can be proteins, peptides, or steroid hormones) directly into the bloodstream.

• These hormones regulate various physiological processes, including mood, growth and development, organ function, metabolism, and reproduction.

Types of Endocrine Gland Arrangements

• Endocrine cells arranged in anastomosing cords:

  • The cells form a network of interconnecting cords or clusters.

  • Examples: Pituitary gland, parathyroid gland, adrenal gland.

• Endocrine cells arranged in rounded follicles:

  • The cells are organized into spherical structures or follicles that store hormones.

  • Example: Thyroid gland.

Role of Endocrine Hormones

Hormones released by endocrine glands play critical roles in maintaining homeostasis by regulating various bodily functions, such as:

• Mood Regulation: Hormones like serotonin and cortisol affect mood and emotional states.

• Growth and Development: Hormones such as growth hormone (GH) and thyroid hormones regulate growth and development.

• Organ Function: Hormones like insulin and glucagon regulate glucose metabolism and energy production.

• Metabolism: Thyroid hormones influence metabolic rate and energy expenditure.

• Reproduction: Hormones such as estrogen, progesterone, and testosterone regulate reproductive processes.