Endocrine System Overview

These flashcards cover key terms and concepts from the lecture on the endocrine system, including hormone functions, signaling mechanisms, and regulatory processes.

Endocrine System

A system of glands that secrete hormones directly into the bloodstream to regulate various functions of the body.

Hormones

Chemical messengers produced by endocrine glands that regulate physiological processes.

Oxytocin

A peptide hormone released from the posterior pituitary that stimulates uterine contractions and milk ejection.

Antidiuretic hormone (ADH)

Also known as vasopressin, it promotes water reabsorption in the kidney and regulates water balance.

Hypothalamus

A region of the brain that controls the pituitary gland and regulates various homeostatic functions.

Anterior Pituitary

The front part of the pituitary gland that produces hormones such as growth hormone and prolactin.

Growth Hormone (GH)

A hormone that stimulates growth, cell reproduction, and regeneration.

Prolactin (PRL)

A hormone released by the anterior pituitary gland that stimulates milk production.

Adrenocorticotropic hormone (ACTH)

A hormone produced in the anterior pituitary that stimulates the adrenal cortex to produce corticosteroids.

Gonadotropic hormones

Hormones that stimulate the gonads, including follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Signal Transduction

The process by which a chemical or physical signal is transmitted through a cell as a series of molecular events.

G protein-coupled receptors (GPCRs)

A large family of receptors that detect molecules outside the cell and activate internal signal transduction pathways.

Peptide Hormones

Hormones made of chains of amino acids that vary in length and function as chemical messengers.

Negative Feedback

A regulatory mechanism in which a change in a physiological variable triggers a response that counteracts the initial change.

Half-life

The time it takes for the concentration of a hormone in the blood to decrease to half its initial value.

Chemical Signaling

The process by which signaling molecules communicate between cells through paracrine, autocrine, and endocrine signaling.

Receptor Regulation

The process by which the number or sensitivity of receptors is adjusted in response to hormone levels.

Bioavailable

The amount of hormone that is available to bind to target cells and exert an effect.

Upregulation

The process by which a cell increases the number of hormone receptors in response to decreased hormone levels.

Downregulation

The process by which a cell decreases the number of hormone receptors in response to prolonged exposure to hormone.

Thyroid Stimulating Hormone (TSH)

A hormone secreted by the anterior pituitary that stimulates the thyroid gland to produce thyroid hormones.

Follicle Stimulating Hormone (FSH)

A hormone that stimulates the growth and maturation of ovarian follicles in females and sperm production in males.