final review(24- Flashcards
mucosa, submucosa, muscularis, serosa
layers of gi tract
inner lining of GI tract
- epithelium protection, secretion, absorption
- lamina propria connective tissue w/ blood and lymphatic vessels and mucosa associated lymphatic
- muscularis mucosa thin layer of smooth muscle making folds to increase surface area
mucosa of gi tract
connective tissue binding to mucosa to muscularis and contains blood and lymphatic vessels [submucosal plexus)
submucosa of gi tract
has voluntary skeletal muscle found in mouth, pharynx, esoph, and anal sphincter; involuntary is elsewhere with myenteric plexus btwn muscle layers
muscularis of gi tract
outermost covering of organs suspended in abdominopelvic cavity aka visceral peritoneum; esophagus lacks serosa bc has adventitia
serosa of gi tract
- Intrinsic set of nerves - “brain of gut”
- Neurons extending from esophagus to anus
- Myenteric plexus – GI tract motility
- Submucosal plexus – controlling secretions
enteric nervous system(digestive) ENS
LARGEST serous membrane of the body : parietal and visceral
peritoneum
secreted by salivary glands acting on starches which only monosaccarides can be absorbed and cont to act until inactivated by stomach acid
salivary amylase
secreted by lingual glands of tongue acts on triglycerides which becomes activated in acidic environment of stomach
lingual lipase
=Mucosa – protection against wear and tear
=Submucosa
=Muscularis divided into thirds
- Superior 1/3 skeletal muscle
- Middle 1/3 skeletal and smooth muscle
- Inferior 1/3 smooth muscle
of esophagus
___ regulates movement into esophagus and ___ regulates movement into stomach
upper esophageal spincter; lower esophageal spincter
act of swallowing; facilitated by secretions of saliva and mucus
STages:
(buccal)voluntary:bolus passed to oropharynx
(pharyngeal):involluntary passage thru pharynx into esoph
(esophagea)l:involuntary passage thru esophagus to stomach using peristalisis pushes bolus forward
deglutition
serves as mixing chamber and holding reservoir; regions include cardia, fundus, body, plyorus
stomach
in mucosa of stomach the exocrine gland cells include
Mucous neck cells (mucus) Parietal cells (intrinsic factor and HCl) Chief cells (pepsinogen and gastric lipase)
- cephalic phase prepares stomach for arrival of food
- gastric phase enhances secretion from 1t phase and initiates digestion of protiens by pepsin
- intestinal phase controls rate of chyme entry into duodenum
phases of gastric secretion
99% of cells are acini [exocrine secrete pancreatic juice mixture of fluid and digestive enzymes]
-1% are pancreatic islets [endocrine secreting hormones glucagon, insulin, somatostatin, and pancreatic polypeptide]
pancreas
major functional cells of liver that secrete bile
hepatocytes
Mostly water, bile salts, cholesterol, lecithin, bile pigments and several ions
Partially excretory product/ partially digestive secretion
bile
- Derived from heme of recycled RBCs
- Breakdown product stercobilin gives feces brown color
bilirubin [principal bile pigment]
small intestine regions include
duodenum, jejunum, ileum
contains absorptive cells , goblet cells (mucus), intestinal glands (intestinal juice), Paneth cells(lysozyme), and enteroendocrine cells
mucosa of small intestine
- Permanent ridges of mucosa and submucosa
- Cause chyme to spiral
plicae circulares of small intestine modificiation
Fingerlike projections of mucosa
-Contains arteriole, venule, blood capillary, and lacteal
villi of small intestine
Fingerlike projections of apical membrane of absorptive cells
Brush border with brush border enzymes
microvillli
- Inserted into plasma membrane of absorptive cells
- Some enzymatic digestion occurs at surface rather than just in lumen
- α-dextrinase, maltase, sucrase, lactase, aminopetidase, dipeptidase, nucleosidases and phosphatases
brush border enzymes
mechanical digestion of small intestine is governed by ___ plexus
myenteric
cecum, colon, rectum, and anal canal with ileocecal sphincter btwn small and large intestine
large intestine
Remove electrons and pass them through electron transport chain to oxygen
oxidative phosphorylation
=oxidation of one glycose molecule to 2 pyruvic acid
=consumes 2 ATP but generates 4
glycolysis
net gain to cell from aerobic catabolism of one glucose molecule is
36 atp
occurs in matrix of mitochondria and is series of redox reactions
krebs cycle or citric acid cycle
Transferring high-energy phosphate group from an intermediate directly to ADP
substrate level phosphorylation
only in chlorophyll-containing plant cells
photophosphorylation
break down complex molecules
Exergonic – produce more energy than they consume
catabolism
combine simple molecules into complex ones
Endergonic – consume more energy than they produce
anabolism
coenzymes that are transferred when hydrogen is liberated
Nicotinamide adenine dinucleotide (NAD)
Flavin adenine dinucleotide (FAD)
- Triglycerides split into glycerol and fatty acids
- Must be done in muscle, liver, and adipose tissue to oxidize fatty acids
- Enhanced by epinephrine and norepinephrine
lypolysis
- Liver cells and adipose cells synthesize lipids from glucose or amino acids
- Occurs when more calories are consumed than needed for ATP production
lipogenesis
pancreatic beta cells release ____ promoting entry of glucose and amino acids into cells
insulin
Fat-soluble – A, D, E, K
Water-soluble – several B vitamins and vitamin C
viitamins
regulates blood ionic comp; blood ph; blood volume; BP;blood osmolarity; produces calcitrol and erythropoitin; reg glucose; excretes wastes from metabolic reactions
kidney functions
Papillary ducts Minor and major calyces Renal pelvis Ureter Urinary bladder
urine formed by nephron drains into
kidney blood supply
renal artery segmental artery interlobar arteries arcuate arties interlobular arteries afferent arterioles glom capillaries efferent arterioles peritubular capillaries interlobularveins arcuate veins interlobar veins renal vein
-filters blood plasma
=Glomerulus – capillary network
=Glomerular (Bowman’s) capsule– double-walled cup surrounding glomerulus
renal corpuscle
– receives filtered fluid
Proximal convoluted tubule
Descending and ascending loop of Henle (nephron loop)
Distal convoluted tubule
renal tubule
-Proximal convoluted tubule cells have microvilli with brush border
renal tubule and collecting duct
___apparatus helps regulate blood pressure in kidney
juxtaglomerular
cells in final part of ascending loop of Henle
macula densa
cells of afferent and efferent arterioles contain modified smooth muscle fibers
juxtaglomerular cells
Last part of ___ convoluted tubule and collecting duct
Principal cells – receptors for antidiuretic hormone (ADH) and aldosterone
Intercalated cells – role in blood pH homeostasis
distal
Water and most solutes in blood plasma move across the wall of the glomerular capillaries into glomerular capsule and then renal tubule
glom filtration
As filtered fluid moves along tubule and through collecting duct, about 99% of water and many useful solutes reabsorbed – returned to blood
tubular reabsorption
As filtered fluid moves along tubule and through collecting duct, other material secreted into fluid such as wastes, drugs, and excess ions and removes substances from blood
tubular secretion
NFP promotes filtration by =
Glomerular blood hydrostatic pressure - capsular hydrostatic pressure - blood colloid osmotic pressure
triggered when JG cells release ___
-renin acts on angiotensinogen to release angi I and converts to II in lungs by ACE which makes arterial pressure rise and stim adrenal cortex to release aldosterone[both sys and glom hydrostatic pressure rise]
renin angiotensinogen system
renin release triggered by reduced stretch of granular JG cells that activated by macula densa cells
renin release
- Released when blood volume and pressure decrease
- Decreases GFR
- Enhances reabsorption of Na+, Cl- and water in PCT
- Stimulates Aldosterone release by adrenal cortex
angiotensin II
Stimulates cells in DCT to reabsorb more Ca2+
parathyroid hormone
inc reabsorption of water, decreasing osmolarity of body fluids
ADH/vasopressin
inc excretion of Na+ in urine, inc urine output and thus decreases blood volume[suppresses ssecretion of ADH and aldosterone]
ANP atrial natriuretic peptide
renal clearance = UV/P
U=conecntration
V-flow rate of urine
P=concentration of same substancei n plasma
volume of blood cleared of a substance per unit time
___ reflex- When volume increases stretch receptors send signals to micturition center in spinal cord triggering spinal reflex where detrusor muscle contracts and internal sphincter relaxes
micturition reflex
\_\_\_= about 2/3 of body fluid \_\_\_= intersitital fluid btwn cell is 80% wiht 20 % plasma in blooddd
ICF;
ECF
- Produced by hypothalamus, released from posterior pituitary
- Permeability to water increases
- Produces concentrated urine
ADH
- ECF most abundant cation is Na+, anion is Cl-
- ICF most abundant cation is K+, anions are proteins and phosphates (HPO42-)
icf/ecf differences
2nd most prevalent ECF anion; regulated by kidneys
bicarbonate
most abundant mineral in body and is regulated by parathyroid hormone/ calcitonin lowers blood calcium levels
calcium
2nd most common ICF cation essential for normal neuromuscular activity, myocardial function, synaptic transmission
magnesium
Act to quickly temporarily bind H+
Raise pH but do not remove H+
Most consist of weak acid and salt of that acid functioning as weak base
buffer systems
dysfunction of respiration
respitatory acidosis
hyperventilation due to oxygen, sever anxiety
resp alkalosis
loss of bicarbonate ions due to diarrhea is
metabolic acidosis
loss of acid due to vomiting
metabolic alkalosis
