Endocrine/Digestive Flashcards
what are the 5 endocrine glands
pitutary, thyroid, parathyroid, adrenal, pineal
what is an exocrine gland
secretes products into ducts or lumens to the outer surface of the body
what is an endocrine gland
secrete products into interstitial fluid which diffuse into blood
what are local hormones
act locally on neighboring cells or the same cell that secreted them
what is paracrine hormone
when the hormone is relsed onto a neighboring cell
what is autocrine signaling
when the hormone is released onto the same cell that secreted it
how do lipid soluble hormones travel in the bloodstream
they have to bind to a protein
what are the two types of circulating hormones
lipid soluble and water soluble
what are the two kinds of lipid soluble hormones
steroid and thyroid hormones’
what are steroid hormones derived from
cholesterol
what are examples of steroid hormones
cortisol, testosterone, estrogen, progesterone, and aldosterone
what are thyroid hormones derived from
a tyrosine ring with iodine attached
what are the two types of water soluble hormones
peptide/protein hormones and biogenic amines
what are examples of peptide hormones
ADH, oxytocin, hGH, TSH, ACTH, insulin, glucagon
where do biogenic amines come from
modified amino acids
what are examples of biogenic amines
NE, epinephrine, dopamine, serotonin, melatonin, histamine
what is the mechanism of lipid soluble hormones
intracellular receptors, this new complex alter gene expression and specific proteins are created in response.
how do peptide hormones work
bind to an receptor on cell surface, trigger a cascade of protein reactions
how does the hypothalamus control the anterior pituitary gland
releases, relesasing hormones or inhibiting hormones that act on cell s in the anterior pituitary
how does the hypothalamus control posterior pituitary gland
hypothalamus relseases other hormones directly into circulation through posterior pitutary
what are the 5 main cell types in the anterior pituitary
somatotrophs, thyrotrophs, lactotrophs, gonadotrophs, corticotrophs
what do somatotrophs secrete
human growth hormone
thyrotrophs secrete
thyroid simulating hormone
lactotrophs secrete
prolactin
gonadotrophs secrete
follicle stimulating hormone and luteinizing hormone
coroticotrophs secrete
adrenocorticotropic hormone and melanocyte stimulating hormone
what happens in the target cells of human growth hormone
increases synthesis of insulin like growth factors
what do insulin like growth factors do
increase cell growth and cell division, uptake amino acids, increase synthesis of proteins, stimulate lipolysis in adipose tissue, decrease glucose in body and save it for brain
what regulates human growth hormone release
GHRH and GHIH
what is stimuli for the releases of GHRH
hypoglycemia, decreases fatty acids, increased amino acids
what is stimuli for the release of of GHIH
hyperglycemia, increased fatty acids and decreased amino acids in blood, high levels of human growth hormone
what does GnRH (gonadotropin releasing hormone) do
stimulates gonadotrophs to produce follicle simulating hormone or luteinizing hormone
what does FSH do in females
stimulates secretion of estrogen, initiates formation of follicle in the ovary
what does FSH do in males
stimulates sperm production
what does LH do in females
secretion of estrogen and progestrone, ovulation, formation of corpus lutetium
what does LH do in males
secretion of testosterone
what does PRH do
stimulates lactotrophs to produce prolactin
what does prolactin do
causes milk production
what does CRH (corticotropin releasing hormone) do
stimulates corticotrophs to release adrenocorticotropic hormone
what does ACTH
stimulates release of glucocorticoids from adrenal cortex
what does TRH do
stimulates thyrotrophs to produce TSH
what does TSH do
stimulate secretion of T3 and T4
does the posterior pituitary gland synthesize hormones
no
what is the posterior pituitary gland made of
two groups of hypothalamic neurons
What are the two hormones released by the posterior pituitary gland
ADH/vasopressin and oxytocin
where is ADH produced
by cells in the supraoptic nucleus
what are the actions of ADH
decreases urine production by stimulating kidneys to return water, prevents water loss in sweat glands, constriction of arterioles
what triggers release of ADH
dehydration or high blood osmolarity
when is ADH inhibited
overhydration or low osmolarity of blood
where is oxytocin produced
cells of the paraventricular nucleaus
describe the regulation of oxytocin during child birth
stretching of the cervix by baby’s head causes the release of oxytocin, the oxytocin causes the uterus to contract, the babys head is pushed further down the cervix causing oxytocin to be released even more
how does oxytocin effect breast feeding
causes milk to be ejected from mammary glands
which thyroid cells produce T3 and T4
follicular cells
what are the actions of thyroid hormones
increases BMR by stimulating cells to use oxygen to make ATP, increased cellular consumption of glucose, fatty acids, and triglycerides. create more Na/K ATPase, enhance actions of sympathetic nervous system
how does thyroid hyposecretion effect children
dwarfism and severe mental retardation
how does thyroid hyposectrion effect adults
edema, low heart rate, muscle weakness, cold, low body temp, weight gain
symptoms of hypersecretion of thyroid
weight loss, nervousness, tremors, increased heart rate and blood pressure, high body temp
what is goiter
enlarged thyroid gland due to lack of iodine in the diet
calcitonin is secreted by what cell in the thyroid gland
parafollicular cells or c cells
what does calcitonin do
lowers blood calcium levels by inhibiting osteoclasts
what cells secrete parathyroid hormone
chief cells in the parathyroid gland
what does parathyroid hormone do
raises blood calcium levels by stimulating osteoclasts, increases reabsorption of calcium by kidneys, promotes formation of calcitriol aka vitamin D
what are the 3 subdivisions of the adrenal cortex from superficial to deep
zona glomerulosa, zona fasciculata, and zona recticularis
what does the zona glomerulosa secrete
mineralocorticoids, mainly aldosterone
what does aldosterone do
increases absorption of Na by kidneys and promotes excretion of K
what does the zona fasciculata release
glucocorticoids mainly cortisol
what does cortisol do
increase rate of protein catabolism and lipolysis, promote gluconeogensis
what else do glucocorticoids do
raise blood pressure by increasing sensitivity of blood vessels to other hormones that cause vasoconstriction
what is cushings syndrome
hypersectrion of glucocorticoids
what is addisons disease
hyposecretion of glucocorticoids
what does the zona recticularis release
androgens
what does the adrenal medulla release
chromaffin cells that reciev direct innervation form the SNS, produce epinephrine and NE
what do the beta cells of the pancreas release
insulin
what do the alpha cells of the pancreas release
glucagon
what is the first layer of the digestive tract
mucosa
What is the purpose of the epithelium in the mucosa layer
secrete enzymes and mucous, enteroendocrine cells
what is the lamina propria
thin layer of loose connective tissue in the mucosa layer
what is the muscularis mucosae
thin layer of smooth muscle that causes folds to form in mucosal layer
what is the second layer of the gi tract
submucosa
what is the submucosa
loose connective tissue conatining blood vessels, glands, and lymphatic tissue
what is the submucosal plexus
part of the enteric nervous system, regulates blood vessel diameter, secretions from glands and neurons
what is the third layer of the gi tract
muscularis
what is the muscularis
a muscle layer that helps to push food through the gi tract
what is the myenteric plexus
found in muscularis layer, part of enteric nervous system
what is the 4th layer of the gi tract
serosa or adventitia
what is the serosa
a serous memebrane aka the visceral perotineum, called adventitia for the esophagaous
what is the parietal peritoneum
lines walls of abdmonial cavity
what is visceral peritoneum
covers organs
what is mastication
chewing
what are two enzymes found in the mouth
salivary amylase and lingual lipase
what are the three major salivary glands
parotid, submandibular, and sublingual glands
what is deglutition
swallowing
what is the voluntary stage
food pushed by tongue into oropharynx
what is pharengyal stage
involuntary
what is the esophageal stage
upper esophageal sphincter relaxes and food goes down by peristalsis
what is gerd
lower esophageal sphincter doesn’t close and food comes back up burning
where are unitary sm cells found
walls of digestive tract, gall bladder, urinary bladder
characteristics of unitary sm cells
autorythmic connect via gap junctions, cell membranes adhere to one another
what are the 4 parts of the stomach
cardia, fundus, body, pylorus
what does gastric surface mucous cell secrete
mucous
what does gastric mucous neck cells secrete
mucous
what does gastric parietal cell secrete
HCl and intrinsic factor
what does gastric chief cell secrete
pepsiongen and gastric lipase
what does G cell secrete
gastrin
what happens to pepsinogen
HCl activates it turning it into pepsin
what is absorbed in the stomach
water, electrolytes, aspirin and alcohol
what branch of the ANS makes stomach contractions more strong
PANS
when is gastrin relseased into the bloodstream
when stomach stretches because of food
what does gastrin do
increase stomach gland secretions and pyloric sphincter relaxation
what are the three part of the small intestine in order
duodenum, jejunum, ileum
what does a si absorptive cell do
absorbs nutrients
what does a small intestine goblet cell do
secretes mucus
what do S cells secrete
secretin
what do CCK cells secrete
cholecystokinin
what do K cells release
GIP
what do panesth cells do
secrete lysozome and is capable of phagocytosis
how are glucose and galactose absorbed
sodium symporter
how fructose absorbed
facilitated diffusion
how does the stomach digest proteins
HCl denatures proteins and pepsin breaks proteins into smaller peptides
what are two brush border enzymes for proteins
aminopeptidase and dipeptidase
how do amino acids get absorbed into the epitheleal cell
active transport using Na or H ions
how are short chain fatty acids absorbed
simple diffusion
what happens to fats once inside an epithelal cell
they are coated with a protein to form a chylomicron
where do chylomicrons go after created
into lacteals, then thru lymphatic system, then to liver
what vitamin has to combine with intrinsic factor before being absorbed
vitamin b12
what is a portal triad
bile duct, hepatic artery, hepatic portal vein
what is the livers functional unit
liver lobule
pathway of bile secretion
bile canaliculi -> bile ducts -> hepatic ducts -> common hepatic duct -> cystic duct + common hepatic duct -> common bile duct -> pancretaic duct
what is gluconeogenisis
turn amino acids into glucose
what is gluconeogenesis
turning glycerol portion of fats into glucose
what is glycogenesis
add excess glucose into glycogen polymer for storage
what is glycogenolysis
breaking off glucose from glycogen polymer
what is deamination
removing NH2 (amine group) from amino acids
what is transamination
converts one amino acid into another
what is haustral churning
when pouches fill with food and then contract and move into the next pouch
what is the gastroilial reflex
when stomach is full and gastrin relaxes the ilem sphincter to let food go into the large intestine
what is the gastrocolic reflex
when stomach fills perstaltic waves move contents from transverse colon in to rectum
what is defecation reflex
when rectum fills u poop
what is the cephalic phase
prepare the mouth and stomach for food, sights of food stimulate gastric juices and salivation
what is the gastric phase
breaking down of food via mechanical and chemical digestion, gastrin is released intot he bloodstream
what is the intestinal phase
intestine starts reving up
what is is secretin
hormone that decreses stomach secretions
what is cholecystokinin
decreses stomach emptying
what is oxidation
decrease in energy of a molecule, electrons are lost
what is reduction
increase in energy content of a molecule, electrons are gained
what is the function of chylomicrons
transport dietary fats to adipose cells
what is the function of VLDL
form in hepatocytes to transport triglycerides to adipose cells
what is the function of LDL
carry blood cholesterol to cells
what is the function of HDL
carry cholesterol from cells to liver for elimination
