Endocrine System Flashcards
– are chemical messengers secreted into the bloodstream that travel to a specific target in the body and change the functioning of that target
hormones
hormones’ target can be individual cells, tissues, or –
organs
hormone secretion is usually regulated via – mechanism
negative feedback
in negative feedback the response of the endocrine system or a target is the – of a stimulus
opposite
two hormones with opposing functions
antagonistic hormones
in positive feedback systems, the response – a stimulus
amplifies
positive feedback mechanisms are – and eventually homeostatic is regained via lack of stimulus
short-lived
– is the main link between the endocrine and nervous systems
hypothalamus
hypothalamus – body conditions and makes changes as needed
monitors
hypothalamus produces – hormones that influence glands such as the pituitary
regulatory
regulates other glands
pituitary
the – of hormones is based on their interaction with a receptor on the target cells
specificity
only cells that have a – for a specific hormone will be affected by that hormone
receptor
because hormones must travel through the blood, making these changes a relatively – process
slow
steroids are – soluble
lipid
non-steroids are – soluble and classified as peptides
water
steroid hormones are derivatives of –
cholesterol
nonsteroid hormones are made of modified – or small proteins
amino acids
target cell receptors for steroid hormones exist in the – of a cell
cytoplasm
target cell receptors for non steroid hormones exist on the – of the cell
cell membrane
another hormone category that are lipid-based molecules released from cell membranes
prostaglandins
prostaglandins function as sort of – hormone involved in diverse functions such as regulation of body temp, blood clotting, menstrual cramping, and inflammatory response
local
T/F: steroids can easily cross the cell membrane
true
steroid-receptor complex moves into the nucleus and interacts with – to cause activation of certain genes
DNA
T/F: nonsteroid hormones cross the cell membrane
false
non steroid hormone itself is termed as a – messenger since it never enters the cell
first
first messengers trigger a series of events within the cell, many of which are moderated by – found on the cytoplasmic side of the plasma membrane
G proteins
inactive G protein
GDP attached to them
When a signaling molecule (like a non steroid hormone) attaches to a G protein-coupled receptor in the plasma membrane, the receptor becomes active and changes –
conformation
conformational change allows the receptor to bind a G protein and activate it by causing it to release its GDP molecule and exchange it for a –
GTP
an activated G protein will dissociate from the receptor and then activate an enzyme called
adenylyl cyclase
when adenylyl cyclase is activated it converts ATP to – which functions as a second messenger
cAMP
second messengers are – that change the function of the target cell by altering enzymatic activities and cellular reactions
nonprotein molecules
cAMP actives a protein called protein kinase A which will proceed to activate other protein kinases in a type of – until the proper protein needed to cause the cellular response to the initial first messenger is activated
phosphorylation cascade
the phosphorylation cascade is shutdown by – that will remove the phosphate groups from the activated proteins, thereby deactivating them and stopping their kinase activity
protein phosphatases
– converts cAMP to ATP thus deactivating cAMP
phosphodiesterase
alpha subunits of G proteins have intrinsic – activity , which will cause the bound GTP to by hydrolyzed to GDP causing the deactivation of the G protein and stopping the further activation of adenylyl cyclase
GTPase
hypothalamus produce regulatory hormones that control the secretion of hormones from the –
anterior pituitary
hypothalamus also makes ADH and oxytocin which are stored and released from the –
posterior pituitary
FSH and LH
anterior pituitary
TSH
anterior pituitary
GH
anterior pituitary
prolactin
anterior pituitary
ACTH
anterior pituitary
endorphins
anterior pituitary
in women, it stimulates the secretion of estrogen and assists in egg production
FSH
in men, it has a role in sperm production
FSH
in women, it stimulates the production of estrogen and progesterone and causes ovulation
LH
in men, it is involved in testosterone secretion
LH
stimulates the thyroid gland
thyroid stimulating hormone (TSH)
stimulates growth of muscle, bone, and cartilage
growth hormone (GH)
stimulates milk production
prolactin (PRL)
stimulates the cortex of the adrenal glands
adrenocorticotropic hormone (ACTH)
act on the nervous system to reduce the perception of pain
endorphins
allows for water retention by the kidneys and decreases urine volume
antidiuretic hormone (ADH) or vasopressin
causes uterine contractions during childbirth; also stimulates milk ejection
oxytocin
influences patterned behaviors such as sleep, fertility, and aging
melatonin (pineal gland)
stimulates the maturation of certain white blood cells involved with the immune system (T cells) decreases with age as the thymus gland atrophies
thymopoietin
stimulates the maturation of certain WBCs involved with the immune system; decreases with ages as the thymus gland shrivels
thymosin
involved in the development of female secondary sex characteristics as well as follicle development and pregnancy
estrogen
involved in uterine preparation and pregnancy
progesterone
a type of androgen needed for the production of sperm as well as for the development and maintenance of male secondary sex characteristics
testosterone
decreases blood sugar after meals by allowing glucose to enter cells to be used for cellular respiration
insulin
a lack of insulin or lack of response by cell receptors to insulin is the cause of –
diabetes mellitus
insulin is made by – of the pancreas
beta islet cells
increases blood sugar levels between meals by allowing for the breakdown of glycogen
glucagon
glucagon is made by – of pancreas
alpha islet cells
made by the heart to lower blood pressure
atrial natriuretic peptide (ANP)
used to regulate blood pressure by altering the amount of water retained by the kidneys
renin/angiotensin
stimulates the production of RBCs from stem cells in the red bone marrow
erythropoietin
released when food enters the stomach; causes the secretion of gastric juice
gastrin
stimulates the release of pancreatic digestive enzymes to the small intestine; also stimulates the release of bile from the gall bladder to the small intestine
cholecystokinin (CCK)
stimulates the release of fluids from the pancreas and bile that are high in bicarbonate to neutralize the acids from the stomach
secretin
placenta secretes
HCG, relaxin, estrogen, and progesterone
signals the retention of the lining of the uterus (endometrium) during pregnancy
human chorionic gonadotropin (HCG)
releases ligament attaching the pubic bones to allow for more space during childbirth
relaxin
placenta releases – and – to maintain pregnancy
estrogen and progesterone
