EXAM I Endocrine System Flashcards
(124 cards)
___ are chemicals secreted by a cell that affects the functions of other cells
hormones
many hormones are derived from ___ that can easily cross the cell membrane
steroids
what are three categories of steroid hormones?
sex, corticosteroids, and mineralocorticoids
what are 3 sex hormones?
estrogen, progesterone, testosterone
what is an example of a corticosteroid? where is it produced?
cortisol, produced in the adrenal cortex
what is an example of a mineralocorticoid? where is it produced?
aldosterone, produced in the adrenal cortex
what are non-steroid hormones made of? can they cross the cell membrane?
they are made of amino acids or proteins, and cannot cross the cell membrane with ease
non-steroid hormones bind to ___. what is usually activated by this complex?
- receptors on the surface of cells
- g-protein is usually activated by the hormone-receptor complex
prostaglandins are ___ hormones, derived from ___
- local
- lipid molecules
prostaglandins typically do not travel in the ___ because ___
- blood stream
- target tissues are located close by
prostaglandins are produced by organs such as ___
kidneys, uterus, heart, brain, and stomach
the basic signal pathway involves a ___ that binds to a ___, which activates ___, which alter ___, creating a ___
- signal molecule
- receptor protein
- intracellular signal molecules
- target proteins
- response
- the target tissue response can be influenced by plasma concentrations and receptor numbers
endocrine activity is partly controlled by the concentration of hormone in ___ and ___. what makes the concentration critical?
blood and extracellular fluid
almost inevitably, disease results when hormone concentrations are either too high or too low, and precise control over circulating concentrations of hormones is therefore critical
___ is the primary mechanism through which the endocrine system maintains homeostasis
negative feedback
plasma glucose levels and the insulin response is an example of ___
negative feedback loops
synthesis and secretion of hormones are the most highly regulated aspect of endocrine control. such control is mediated by ___ and ___
positive and negative feedback circuits
target response is based on ___ and ___
receptor numbers and the presence of other different hormones
___ is the decrease of hormone receptors which decreases the sensitivity to that hormone
down-regulation
___ is the increase in the number of receptors which causes the cell to be more sensitive to a particular hormone
up-regulation
what are the 3 general roles of the hypothalamus in homeostasis?
- receives sensory information from the thalamus
- hypothalamus monitors the body for temperature, pH, and other conditions
- hypothalamus signals pituitary gland if conditions need to be corrected
- hypothalamo-pituitary portal system
- neurosecretory innervation
the ___ gland is located at the base of the brain and is controlled by the hypothalamus, and is protected by a bony structure called the ___
- pituitary
- sella turcica
the optic chiasm is located just above the ___
pituitary gland
the pituitary gland is divided into which two lobes?
anterior and posterior lobes
the ___ is the “master gland” that signals other glands to produce their hormones when needed
pituitary gland