Unit 3 Flashcards
(129 cards)
Endocrine Glands
gland that secretes hormones into the bloodstream to act on distant targets
-secrete the principal hormones
-Leydig and Sertoli cells in testies
Pheramones
A chemical signal that is released outside the body of an animal and affects other members of the same species
Allamones
A chemical signal that is released outside the body by one species and affects the behavior of other species
Peptide Hormone (AKA protein hormone)
A hormone that consists of a string of amino acids
-Cannot come and go as pleases
Amine Hormone (AKA monoamine hormone)
A hormone composed of a single amino acid that has been modified into a related molecule
-melatonin or epinephrine
Steroid Hormone
Any of a class of hormones, each of which is composed of four interconnected rings of carbon atoms
-Dissolves readily in lipids, can pass through membranes easily.
Generally located inside the target cell
Second Messenger
slow-acting substance in target cell that amplifies the effects of synaptic/hormonal activity and regulates activity in target cell.
-Peptide and amine hormones bind to receptor proteins on surface of target cell and activate second messengers
Pituitary Gland
Endocrine gland at the base of the skull.
-Hypothalamus is connected via the pituitary stalk.
-Regulates most other endocrine glands (Deemed The Master Gland)
Neuroendocrine Glands
neuron that releases hormones into local or general circulation via bloodstream
Posterior Gland
The rear division of the pituitary gland
-the supraoptic and paraventricular nuclei
Transport hormones down their axons, which extend through the pituitary stalk to terminate in the posterior pituitary
-Release two peptide hormones: oxytocin and vasopressin
Oxytocin
A peptide hormone, released from the posterior pituitary
-Triggers milk letdown
Negative Feedback
The process whereby a system monitors its own output and reduces its activity when a set point is reached.
-Like a thermostat
Anterior Pituitary
The front division of the pituitary gland. It secretes tropic hormones
Tropic Hormones
Anterior pituitary hormones that affect the secretion of hormones by other endocrine glands
- travels throughout the bloodstream, reaching all glands, but only the target glands have the appropriate receptors to respond to it. The gland then releases its own hormones
Releasing hormones
Hormones produced in the hypothalamus, that traverse the hypothalamic-pituitary portal system to control the pituitary’s release of tropic hormones
Vasopresin
peptide hormone from posterior pituitary
-Promotes water conservation and increases blood pressure
Milk Letdown
The reflexive release of milk by the mammary glands of a nursing female in response to stimuli associated with suckling.
-Oxytocin
Median Eminence
the point at which the pituitary stalk exits the hypothalamus to connect to the pituitary
-Where axons of these neuroendocrine cells converge
Hypothalamic-Pituitary Portal System
-in response to input, axon terminals of the hypothalamic neuroendocrine cells secrete releasing hormones into the local bloodstream
-Blood carries releasing hormones into the anterior pituitary
-anterior pituitary cells release tropic hormones into general circulation
-tropic hormones regulate activity of major endocrine organs in body
Gonadotropin-Releasing Hormone (GnRH)
Hypothalamic hormone that controls the release of (LH) and (FSH) from the pituitary (arrives at the anterior pituitary)
Follicle-Stimulating Hormone (FSH)
A gonadotropin, named for its actions on ovarian follicles
-tropic hormones
F: stimulates growth and maturation of egg-containing follicles and secretion of estrogens
M: FSH governs sperm production
Luteinizing hormone (LH)
A gonadotropin, named for its stimulatory effects on the ovarian corpora lutea (secretes the sex steroid hormone progesterone)
M: stimulates the testes to produce T
Proceptive
Readiness to mate through species-typical behaviors
M: staying near the females, sniffing face or vagina
F: approach males, remain close to them, or show alternating approach and retreat behaviors
Copulation/Coitus
transfer of sperm from a male to a female