CHAPTER 6-THE ENDOCRINE SYSTEM: ENDOCRINE GLANDS AND HORMONE ACTIONS

This set of flashcards covers key concepts and vocabulary related to the endocrine system, its glands, hormones, and their actions.

Endocrine Glands

Organs that secrete hormones directly into the bloodstream.

Primary Endocrine Organs

Organs whose primary function is the secretion of hormones, such as the pituitary gland.

Secondary Endocrine Organs

Organs that secrete hormones as a secondary function, having other primary roles, such as the kidneys.

Hormones

Chemical messengers secreted into the blood that transport signals to distant cells.

Hypothalamus

Part of the brain and a primary endocrine gland that secretes hormones affecting the pituitary gland.

Pituitary Gland

A pea-sized primary endocrine gland divided into anterior and posterior lobes that regulates various body functions.

Anterior Lobe

The lobe of the pituitary gland made up of epithelial tissue, secretes tropic hormones.

Posterior Lobe

The lobe of the pituitary gland composed of nerve tissue that stores and releases oxytocin and antidiuretic hormone.

Oxytocin

A peptide hormone released during childbirth that increases uterine contractions.

Antidiuretic Hormone (ADH)

Hormone that increases water reabsorption in the kidneys and is stimulated by high plasma solute concentration.

Tropic Hormones

Hormones that regulate the secretion of other hormones from different endocrine glands.

Hypothalamic-Pituitary Portal System

A network of blood vessels allowing tropic hormones from the hypothalamus to directly affect the anterior pituitary.

Melatonin

Hormone secreted by the pineal gland that establishes circadian rhythms.

Thyroid Hormone

Hormones (Tetraiodothyronine and Triiodothyronine) that regulate metabolism, growth, and development.

Parathyroid Hormone

Hormone that stimulates bone cells to release calcium into the bloodstream.

Thymosin

Hormone secreted by the thymus gland that plays a key role in programming T Lymphocytes.

Adrenal Cortex

The outer region of the adrenal glands that produces mineralocorticoids, glucocorticoids, and androgens.

Epinephrine

Also known as adrenaline, a hormone that increases heart rate during stress.

Insulin

Hormone secreted by the pancreas that regulates blood glucose levels.

Glucagon

Hormone that increases blood glucose levels by stimulating glycogen breakdown in the liver.

Testosterone

Male hormone secreted by the testes that regulates male characteristics and reproductive functions.

Estrogen

Hormone secreted by the ovaries that regulates female characteristics and reproductive functions.

Hypersecretion

Excessive secretion of hormones that can lead to adverse health effects.

Hyposecretion

Reduced secretion of hormones that can result in significant health issues.

Negative Feedback Loop

A regulatory mechanism where an increase in a hormone leads to a decrease in its secretion.