Endocrine System - Anatomy and Physiology - Test #3

exocrine gland

have ducts - sweat, oil, mucous, digestive

endocrine gland

ductless glands - secrete to interstital fluid capillaries - blood

hormone

chemical messangers; secreted by glands into the bloodstream that regulate various physiological processes.

target cells

cells that have receptors for specific hormones, allowing them to respond to hormonal signals; fast or slow effect; effect can last seconds, hours, days

receptor sites

specific protein structures on target cells that bind to hormones, initiating a cellular response

lipid soluble

(mechanism of hormone action) in cell on genes; enters bloodstream to cell through cell mebrane lipid bilayer - if target cell - hormone binds to and activates receptors in cytosol - gene expression is altered - a new protein product is made - cell activity is altered

steroid

hormones derived from cholesterol that are lipid soluble and can pass through cell membranes to activate gene expression

thyroid

hormones produced by the thyroid gland that regulate metabolism, growth, and development

NO

Nitric Oxide, a signaling molecule that acts as a hormone, playing roles in vasodilation and neurotransmission

water soluble

(mechanism of hormone action) 1st messenger; enters bloodstream - to cell reaches plasma membrane - membrane protein (G protein) is activated - G protein → adenylate cyclase an enxyme that converts ATP to cyclic AMP in to cytsol - cAMP is the secondary messanger which adds phosphate to proteins in the cell - there is a physiologival response - then cAMP is deactivted

amine

hormones derived from amino acids, including neurotransmitters like dopamine and epinephrine, that play various roles in the body

peptide/protein

hormones made of chains of amino acids, playing crucial roles in body functions such as growth, metabolism, and regulation of physiological processes

permissive effect

a phenomenon where one hormone enhances the effect of another hormone, allowing a greater physiological response

synergistic effect

a phenomenon where two hormones work together to produce a greater effect than either would alone

antagonist

a hormone that opposes the action of another hormone, inhibiting its effects on the target cells

hypothalmus

The hypothalamus is a small region of the brain that plays a crucial role in maintaining homeostasis by regulating various physiological functions, including temperature, hunger, and the release of hormones from the pituitary gland.

infundibulum

a stalk-like structure that connects the hypothalamus to the pituitary gland, facilitating the transport of hormones between them

connection to the pituitary

gland via the infundibulum

hypophysis

another name for the pituitary gland, responsible for hormone production and secretion

negative feedback system

a regulatory mechanism in which a hormone's effects inhibit its own production, maintaining homeostasis

positive feedback system

a regulatory mechanism where the effects of a hormone enhance its own production, often leading to a specific outcome or event