Term
| ________ is an enzyme that converts angiotensinogen into angiotensin I. |
|
Definition
|
|
Term
The hormone
-induced increases in water permeability of the distal tubule and/or collecting ducts is mediated by a(n) ________. |
|
Definition
increase in aquaporin
-2 activity |
|
|
Term
| What is the process whereby molecules are selectively transported from the peritubular fluid to the lumen of the renal tubules? |
|
Definition
|
|
Term
| During myogenic regulation of glomerular filtration rate, an increase in mean arterial pressure will ________. |
|
Definition
| cause the afferent arterioles to constrict and thereby maintain a relatively constant glomerular filtration pressure |
|
|
Term
| The ________ is the functional unit of the kidney |
|
Definition
|
|
Term
| What two structures make up the renal corpuscle? |
|
Definition
| Bowman's capsule and glomerulus |
|
|
Term
| The strongest stimulus for the release of antidiuretic hormone from the posterior pituitary is a(n) ________. |
|
Definition
| increase in plasma osmolarity |
|
|
Term
| The regulation of sodium and water balance in the kidneys occurs primarily through the unique action of the ________ cells in the distal tubules and collecting ducts. |
|
Definition
|
|
Term
| After fluid passes through the entire proximal tubule, the fluid will enter the ________. |
|
Definition
|
|
Term
The intracellular event that stimulates the insertion of aquaporin
-2 into the apical membrane of the principal cell is driven by ________. |
|
Definition
|
|
Term
| The cellular changes that occur in response to an increase in blood aldosterone concentration involve a(n) ________. |
|
Definition
increased number of open Na
+ and K+ channels in the apical membrane |
|
|
Term
| Blood leaves the glomerulus and enters the ________. |
|
Definition
|
|
Term
| Aldosterone is released from the ________ in response to ________. |
|
Definition
| adrenal cortex: increases in plasma potassium |
|
|
Term
| During what process are molecules selectively removed from the tubule lumen, moved into the interstitial space, and removed from the kidneys by the peritubular capillaries and the vasa recta? |
|
Definition
|
|
Term
| Once produced, urine travels through the ________ until it reaches the bladder, from which it is released into the external environment by the ________. |
|
Definition
|
|
Term
|
Definition
-Secrete erythropoietin(used to make red blood cells from bone marrow)
-Secrete renin
-Activate Vitamin D3 to calcitriol
-gluconeogenesis(makes new glucose) |
|
|
Term
| The parts of the Urinary system |
|
Definition
Kidneys-(filters blood)form urine
Ureters-transport urine from kidneys to bladder
Bladder-stores urine
Urethra-excrete urine from bladder to outside of body |
|
|
Term
|
Definition
Paired, bean shaped
About the size of fist, 115-170grams
Retroperitoneal(back below rib cage) |
|
|
Term
|
Definition
Renal arteries enter kidney at hilus
Receive 20% of cardiac output at rest(about 1 liter per minute at rest)
-Less than 1% of body weight(so you know it is important)
Uses 16% of ATP usage by body(almost as much as the brain)
Function is to filter blood
Renal veins exit at hilus |
|
|
Term
| Microscopic anatomy of the kidneys |
|
Definition
Nephron(functional unit of kidney) About 1.2 million in each kidney
Renal corpuscle(Bowman's capsule and glomerulus) and renal tubules |
|
|
Term
|
Definition
Glomerulus=Capillary network for filtration
Bowman's capsule=receives the filtrate, inflow to renal tubules |
|
|
Term
|
Definition
Proximal tubule(Proximal convoluted tubule, proximal straight tubule)
Loop of Henle(desceding limb, thin-ascending limb, thick ascending limb)
Distal convoluted tubule(connecting tubule) Collecting duct |
|
|
Term
|
Definition
Long loop of Henley extends into medulla
Responsible for the meullary osmotic gradient(favors movement of water) |
|
|
Term
|
Definition
Short loop of Henle
Most numberous, 80-85%
Have to have both Cortical and Juxtamedullary nephrons to survive |
|
|
Term
| Juxtaglomerular apparatus |
|
Definition
| If we vasodialate the Afferent=get blood out of kidneys quicker If we vasoconstrict the Efferent=keep blood in kidneys longer and produce more urine |
|
|
Term
| Basic renal exchange processes |
|
Definition
Glomerular filtration(Corpuscle)=from glomerulus to Bowman's capsule
Reabsorption=(bring back into body)from tubules to peritubular capillaries
Secretion=(lost as urine)from peritubular capillaries to tubules(capillaries to nephron)
Excretion- from tubules out of body |
|
|
Term
|
Definition
Bulk flow of plasma
Glomerular capillaries to renal capsule
Your urine is completely sterile
You can drink your urine if you absolutley have to in order to survive, but don't drink it more than once in a row. The second time around it will be very little water, mainly waste. |
|
|
Term
|
Definition
Movement of protein-free plasma from glomerulus to Bowman's capsule
GFR=125mL/min or 180 liters/day
Only 1.5 liters urine excreted/day(<1%)
99% of fluid is reabsorbed
Small increase in GFR->large increase volume fluid filtered and excreted
GFR is highly regulated-->
-myogenic regulation(comes from smooth muscles)
-tubuloglomerular feedback
-regulates over a large variety of pressures
Body favors reabsorption of water |
|
|
Term
|
Definition
Smooth muscle in wall of afferent arteriols
Contracts in response to stretch(recoil) |
|
|
Term
| Tubuloglomerular feedback |
|
Definition
Macula densa cells secrete paracrine in response to an increase in flow of fluid past them
Smooth muscle of arteriole contract in response to this paracrine |
|
|
Term
| Functions of the urinary system |
|
Definition
Regulate plasma ionic composition(Na,K...)
Regulate plasma volume
Regulate plasma osmolarity(thickness of blood)
Regulate plasma pH
Remove metabolic waste product and foreign substances from plasma(drugs and narcotics) |
|
|
Term
|
Definition
Most occurs in proximal convoluted tubule
Some in distal convoluted tubule
Barrier for reabsorption-->
-Epithelial cells of renal tubules
-Endothelial cells of capillary(minimal) |
|
|
Term
|
Definition
Solute moves from peritubular capillaries into tubules
Barriers same as for reabsorption
Transport mechanisms same but opposite direction
Secreted substances
-Potassium
-Hydrogen ions
-Choline(byproduct of acetylcholine)
-Creatinine
-Penicillin |
|
|
Term
| Water conservation due to Loop of Henle |
|
Definition
Loop of Henle established conditions necessary to concentrate urine
Loop of Henley cuts water loss to a minimum |
|
|
Term
|
Definition
Micturition=Urination
Urine formed in renal tubules
Fluid drains into renal pelvis and into ureter
Ureter leads to bladder
Bladder stores urine until it is excreted |
|
|
Term
| Regulated waste reabsorption |
|
Definition
When membrane of late DCT and CD is impermeable to water
Water CANNOT leave the tubules
No water reabsorption
More water is excreted in urine
ADH stimulates the insertion of water channels(aquaporin-2) into apical membrane
Water is reabsorpbed by osmosis
Maximum urine concentration is 1400mOsm
ADH comes from neurohypyphasis |
|
|
Term
| Regulation of ADH release |
|
Definition
ADH=posterior pituitary hormone
Released from neurosecretory cells originating in hypoghalamus
Primary stimulus for release
-Increased osmolarity(osmoreceptors(thickness of blood))
Other stimuli
-Increase blood pressure(baroreceptors)
-Increased blood volume(volume receptors)
No ADH-No aquaporin-2(AQP2)
Alcohol is the largest diurettic because it blocks ADH which blocks AQP2 which causes contant urination |
|
|
Term
|
Definition
|
|
Term
|
Definition
Low plasma sodium
We can get this way through exercise
University of Florida made Gatorade in the 70's to help football players balance electrolytes, it worked.
Now original formula of Gatorade is only available in powder. They now have G1, G2...etc because people were drinking Gatorade just as a regular drink but it is like drinking 2-3 cans of pop. G1,2 have less sodium and less sugar to help with obesity. |
|
|
Term
|
Definition
Hypernatremia
Hyponatremia
Sodium-primary solute in extracellular fluid
-Critical to normal osmotic pressure
-Critical to function of excitable cells
Body doesn't like to lose water
Salt and water always go together |
|
|
Term
|
Definition
Freely filtered(passive transport)
Reabsorbed in proximal tubule, distal tubule, and collecting duct
No secretion |
|
|
Term
| Regulation of sodium reabsorption |
|
Definition
Sodium reabsorbed in proximal tubule(70%) and distal tubule and collecting ducts
Reabsorption regulated by aldosterone and ANP
Reabsorption regulated at principal cells of distal tubule and collecting duct
Sodium will never be put in urine by body, body wants to hold onto sodium
Sodium reabsorption
-Active reabsorption
-Na+/K+ pump on basolateral membrane drives reabsorption |
|
|
Term
| Effects of Aldosterone on sodium reabsorption |
|
Definition
Aldosterone increases sodium reabsorption
Steroid homone
Secreted from adrenal cortex
Acts on principal cells of distal tubules and collecting ducts
-Increases number of Na+/K+ pumps on basolateral membrane
-Increases number of open Na+ and K+ channels on apical membrane |
|
|
Term
| Renin-Angiotensin-Aldosterone system |
|
Definition
Granular cells of JGA secrete renin
Capillary walls contain angiotensin converting enzyme(ACE)
Liver secretes angiotensinogen
Regulated by kidney Afferent |
|
|
Term
| Atrial Natriuretic Peptide(ANP) |
|
Definition
Secreted by atrial cells in response to distention of atrial wall
Increase GFR
-Dilation of afferent arteriole
-Constriction of efferent arteriole
Decreases sodium reabsorption by closing sodium channels in apical membrane
Overall effect: Increased sodium excetion
Gravity reduces loss of water
NASA made Tang to help astronauts not faint when returning to earth's atmosphere
Tang is salty which holds onto water in the body. |
|
|
Term
|
Definition
|
|
Term
|
Definition
Low plasma potassium
Potassium is crutial to function of excitable cells |
|
|
Term
| Renal handling of potassium ions |
|
Definition
Glomerulus-freely filtered
Proximal tubules-reabsorbed
Distal tubules and collecting ducts- reabsorbed and secreted
Potassium secretion in distal tubules and collecting ducts is regulated
Aldosterone regulates principal cells
-Primary affects potassium
-Secondary affects sodium |
|
|
Term
| Regulation of aldosterone release |
|
Definition
Renin-angiotensin-aldosterone system
K+ in plasma directly stimulates aldosterone release
-As K+ increases, more aldosterone released |
|
|
Term
|
Definition
Hollow tube
15 feet long
Mouth->pharynx->esophagus->stomach->small intestine->colon->rectum->anus |
|
|
Term
|
Definition
Four layers
-Mucosa(inner layer) lines lumen
-Submucosa- Connective tissue
-Muscularis externa(two types of muscles-circular which mixes bolus, and longitudinal which moves the bolus down the GI tract)
Serosa-connective tissue |
|
|
Term
|
Definition
Digestion begins with mastication(chewing)
Secretion=saliva
-Lubricant
-Salivary amylase-digestive starch and glycogen |
|
|
Term
|
Definition
Also known as the throat
Common passageway for air and food
Food enters via the esophagus |
|
|
Term
|
Definition
Muscular tube from pharynx to stomach
Upper 1/3-skeletal muscle
Lower 2/3-smooth muscle
Upper esophageal sphincter(skeletal muscle)
Lower esophageal sphincter(smooth muscle) between esophagus and stomach |
|
|
Term
|
Definition
Stores food after swallowed
Empty volume=50mL
Full volume=100mL
Secretes gastric juice
Releases food into intestine slowly
Fundus
Body
Antrum
Contractions
-Mix chyme(circular)
-Gastric emptying(longitudinal) |
|
|
Term
|
Definition
Secretory products
-Pepsinogen secreted by cheif cells
--Precursor for pepsin, enzyme that digests proteins
Hydrogen ions secreted by parietal cells
-Maintain acidic environment of stomach
Intrinsic factor secreted by parietal cells
-Necessary for absorption and breakdown of Vitamin B12(only comes from animal stomach)
Gastrin secreted from G cells(hormone)
Mucus secreted from neck cells |
|
|
Term
| Acidic environment of stomach |
|
Definition
pH=2
Necessary for activating pepsinogen
Denatures proteins
Kills bacteria(if bacteria is not killed, you will be sick)
Gastric mucosal barrier
-Protective layer of mucus and bicarbonate(base)
-Secreted from neck cells and goblet cells
If mucus and bicarbonate layer is eaten away, we have ulcers |
|
|
Term
|
Definition
| Regulates passage of chyme between stomach and small intestine |
|
|
Term
|
Definition
Coiled, hollow tube
8-10 feet long
Between stomach and large intestine
Primary site of digestion and absorption
Three divisions
-Duodenum
-Jejunum
-Ileum |
|
|
Term
|
Definition
Pancreatic juice enters duodenum
-Digestive enzymes
-Bicarbonate(neutralizes acidic chyme)
Bile enters duodenum
-Secreted from liver
-Can be stored in gallbladder
Contains bile salts which aid in fat digestion |
|
|
Term
| Absorption in small intestine |
|
Definition
Absorption completed within first 20% of intestine length(most in duodenum, some in jejunum, none in ileum)
Anatomically arranged for large surface area for absorption |
|
|
Term
|
Definition
Villi increase surface area of epithelium
-Contain blood vessels and lacteal for absorption of nutrients
Microvilli increase surface area of epithelial cells
-Form brush border |
|
|
Term
|
Definition
Liver makes bile
Absorbed nutrients travel in blood to liver before entering general circulation
Liver functions to detoxify substances and processes certain nutrients |
|
|
Term
|
Definition
Vasculature that delivers absorbed nutrients to liver before entering general circulation
Nutrients absorbed from small intestine into mesenteric veins
Nutrients travel from mesenteric veins to liver via hepatic portal vein
Nutrients travel from liver to heart(general circulation) via hepatic vein
Hepatic artery provides liver with fresh blood to supply oxygen |
|
|
Term
|
Definition
Hollow tube from small intestine to rectum
Functions
-Concentrates waste into feces
-Absorption of most water
-Store feces until defication
Internal anal sphinctor is controled by smooth muscle
External anal sphinctor is controled by skeletal muscle
Four sections
-Ascending colon
-Transverse colon
-Descending colon
-Sigmoid colon |
|
|
Term
|
Definition
Large intestine=cecum, colon, and rectum
Ileocecal spincter is between ileum and colon
Teniae coli are bands of longitudinal smooth muscles(slowly squeezing water out of food stuff) |
|
|
Term
|
Definition
Colon empties into rectum, then feces excreted through anus
Colon, rectum, and cecum=large intestine
Internal anal sphincter=smooth muscle
External anal sphincter=skeletal muscle
Relaxation of BOTH sphincters necessary to open and excrete feces=defication |
|
|
Term
|
Definition
Secreted products via ducts into the lumen of the GI tract
Include the following
-Salivary glands which secreted saliva
-Pancreas which secretes pancreatic juice
-Liver which secretes bile |
|
|
Term
| Characteristics of saliva |
|
Definition
Rich in bicarbonate ions
Contains mucus
Enzymes
-Salivary amylase
-Lysozyme |
|
|
Term
| ________ cells are responsible for secreting pepsinogen into the lumen of the stomach. |
|
Definition
|
|
Term
| The presence of food in the duodenum will cause ________ secretion to increase, which decreases the sensation of hunger. |
|
Definition
|
|
Term
| Which of the following is the correct order of the layers of the gastrointestinal tract wall, from lumen to external surface? |
|
Definition
mucosa
submucosa muscularis externa serosa |
|
|
Term
| The technical word for chewing is ________. |
|
Definition
|
|
Term
| ________ cells function to secrete hydrogen ions into the lumen of the stomach. |
|
Definition
|
|
Term
| Which of the following is the correct order of the components of the small intestine, from stomach to colon? |
|
Definition
duodenum
jejunum ileum |
|
|
Term
| Which lipoprotein increases the risk for the development of CVD due to it's mobility? |
|
Definition
|
|
Term
|
Definition
| folds in the stomach that can flatten to expand the stomach volume |
|
|
Term
| The digestion of proteins begins in the ________ with the activation of the zymogen ________. |
|
Definition
|
|
Term
Gastric
-phase control of gastrointestinal function refers to its site of origin ________. |
|
Definition
|
|
Term
| The secretion of leptin causes ________. |
|
Definition
| decreased sensation of hunger |
|
|
Term
| Leptin is a strong stop eating signal. What happenned once it was produced in a lab and sold to Johnson and Johnson? |
|
Definition
| It worked in animals very well, but didn't do anything in humans. |
|
|
Term
| As the food is broken into smaller pieces in the mouth, it is combined with ________ that facilitates its movement down the esophagus. |
|
Definition
|
|
Term
One of the degradation by
-products of hemoglobin, ________, is removed from the liver (and thereby the body) in bile. |
|
Definition
|
|
Term
| ________ are enzymes secreted by the exocrine pancreas to degrade fats. |
|
Definition
|
|
Term
| Which of the following is a ring of skeletal muscle that regulates the movement of a bolus into the esophagus? |
|
Definition
| upper esophageal sphincter |
|
|
Term
| Which of the following secretes primarily lipase enzymes? |
|
Definition
|
|
Term
| The hormone ______ is a start eating signal that will cause one to eat without consequence. (abbreviation only please) |
|
Definition
|
|
Term
|
Definition
Has exocrine(bicarbonate, enzymes) and endocrine(alpha, beta, glucagon..)portions
Exocrine portions produce pancreatic juice rich in pancreatic amylase and lipases, proteases, nucleases |
|
|
Term
|
Definition
Precurser for pepsinogen
Inactive forms of digestive enzymes
Stored in zymogen granules of acinar cells
Activated, usually by proteolytic enzymes, in lumen of intestinal tract |
|
|
Term
|
Definition
Secrete bile
Processing of nutrients
-Glucose->glycogen
-Amino acids->fatty acids
-Triglycerides and cholesterol synthesis
-Lipoprotein synthesis
Removal of old red blood cells(assists the spleen)
-Catabolize hemoglobin
-Generates bilirubin
Elimination of wastes and toxins
-Bilirubin eliminated as bile pigments
Synthesis of plasma proteins
Secretion and modification of hormones
No functioning liver=build up of old red blood cells=jaundice |
|
|
Term
|
Definition
Liver, gallbladder, and associated ducts
Liver synthesizes bile
Gallbladder stores bile
Common bile duct transports bile from liver and/or gallbladder to duodenum
Joins with pancreatic ducts to form Ampulla of Vater
Sphincter of Oddi regulates flow from pancreas and gallbladder to duodenum |
|
|
Term
|
Definition
Materials to make bile taken up from blood in sinusoids(hollow cavities) into hepatocytes
Hepatocytes secrete bile into bile canaliculi, on side opposite of sinusoids
Canaliculi drain into bile ducts
Bile ducts drain into common hepatic ducts |
|
|
Term
|
Definition
Regulation of GI function is NOT based on the concept of homeostasis
Regulate GI function to maximize absorption regardless of whether nutrients are needed
Regulate conditions in lumen of GI tract to maximize absorption
GI tract favors food-when it gets it, its job is to pull out as much nutrients from the food that it can. |
|
|
Term
| Neural and endocrine pathways |
|
Definition
Enteric nervous system
-Submucosal plexus
-Myenteric plexus
-Reflexes mediated through ENS controls many GI functions
CNS contributions to neural control
-Generally through communication of ANS with enteric nervous system
GI hormones secreted from endocrine cells in stomach and small intestine
Sensory receptors in GI tract detect environment in lumen to initiate reflexes |
|
|
Term
|
Definition
| Basically it shuts off your stomach and prepares your small intesines for food. |
|
|
Term
| Phases of gastrointestinal control |
|
Definition
Cephalic phase-stimuli originate in head(thoughts, taste, smell)
Requires input from CNS(long reflexes)
Gastric phase-stimuli originate in stomach(long and short reflex and GI hormones)(breaks down food)
Intestinal phase-stimuli originate in small intestine(absorption)
Long and short reflex and GI hormones |
|
|
Term
| Short-term regulation of food intake |
|
Definition
Hunger versus satiety
Satiety factors=insulin, CCK, neural input from mechano-and chemo-receptors
CCK takes about 15 minutes to tell your brain to stop eating. Drink water or eat a salad first and eat slowly, you can cut your calories almost in half by doing this. |
|
|
Term
| Long-term regulation of food intake |
|
Definition
Leptin=hormone released from adipose cells when calories exceeds demand
Leptin suppresses hunger and increases metabolism.
NPY tells us to START eating. If we were to inject NPY into our brain it would make us eat everything around without concern for our well being.
Leptin helped lab rats to lose weight, but when it was put into pill form, it didn't work on humans. |
|
|
Term
| Gastrointestinal secretion and its regulation |
|
Definition
Saliva secretion
Acid and pepsinogen secretion in the stomach
Secretion of pancreatic juice and bile
Rates of fluid movement in the digestive tract |
|
|
Term
|
Definition
Taste and texture of food->mechanoreceptors and taste receptors in mouth->salivary center of medulla->autonomic nervous system->stimulate salivation
When you smell cooking, or think of cooking you start to salivate |
|
|
Term
| Autonomic input to salivary glands |
|
Definition
Parasympathetic->watery saliva
Sympathetic->more mucus, thick saliva(cotton mouth)
You can tell if someone is high through there saliva |
|
|
Term
|
Definition
Parietal cells produce hydrochloric acid
-Carbonic anhydrase catelyzes production of bicarbonate and H+
-H+ are actively secreted into lumen of stomach
-Bicarbonate is transported into interstitial fluid for Cl-
-Cl- diffuses into lumen of stomach through channels
Net result of acid production
-H+ and Cl- are secreted into lumen of stomach(forms hydochloric acid)
-Bicarbonate enters the interstitial fluid and then blood |
|
|
Term
| Regulation of acid secretion into stomach |
|
Definition
Stimulate acid secretion
Parasympathetic nervous system
Gastrin(activate and prepare stomach for digestion)
Histamine(paracrine) |
|
|
Term
| Regulation of pepsinogen secretion into stomach |
|
Definition
Pepsinogen secretion regulated in sync with acid secretion
-Parasympathetic nervous system
-Gastrin
-Histamine
If acid goes up, pepsinogen goes up too! |
|
|
Term
| Cephalic-phase regulation of secretion |
|
Definition
Stimuli increase acid and pepsinogen secretion
-Sight of food, taste, smell, chewing, swallowing(all of this plus just the thought of food make you start to salivate)
All activate parasympathetic nervous system
Parasympathetic nervous system stimulates gastrin secretion |
|
|
Term
| Gastric-phase regulation of secretion |
|
Definition
Stimuli of gastric secretion: proteins, peptides, and amino acids, distension of stomach
Short and long reflex pathways trigger gastrin, acid, and pepsinogen release |
|
|
Term
|
Definition
Gastric phase
-Exit of food removes stimuli for secretion
-Increased acidity inhibits gastrin release
Prepares for intestinal phase
Intestinal phase
Entry of food into duodenum causes
-Increased osmolarity, fat and acid, distension
Long and short term reflex pathways inhibit acid and pepsinogen secretion
Shuts off gastric phase, no longer need acid and pepsinogen |
|
|
Term
| Stimuli for CCK and secretin release |
|
Definition
Stimuli for CCK release
-Fat and amino acids in duodenum
Stimuli for secretin release
-Acidity in duodenum
CCK goes up, secretin goes up as well |
|
|
Term
| Regulation of bile secretion into duodenum |
|
Definition
Secretin-stimulates bile secretion from liver
CCK-stimulates gallbladder contraction, stimulates relaxation of sphincter of Oddi
Emulsification=to make smaller, increase surface area to make it more manageable
Need both CCK and secretin |
|
|
Term
|
Definition
Movement of the wall of the GI tract
Due primarily to the contractions of the muscularis externa(outer muscle layers)-two layers of muscle; circular(mix), longitudinal(propel)
Function: to mix and propel |
|
|
Term
|
Definition
Squeeze and propel forward
Requires circular and longitudinal muscle |
|
|
Term
|
Definition
Squeeze and propel forward
Requires circular and longitudinal muscle contractions
Proximal segment
-Circular muscle contracts; longitudinal muscle relaxes
-Diameter decreases
Distal segment
-Circular muscle relaxes; longitudinal muscle contracts
-Diameter increases
Contents propelled forward from small diameter to large
Only ONE direction |
|
|
Term
|
Definition
Circular only
A type of motility of the small intestine
Requires circular muscle layer
Alternating contractions between intestinal segments
Mixes chyme |
|
|
Term
|
Definition
Voluntary and involuntary control
Chewing reflex-cyclical reflex
-Normally, jaw muscles active-hold mouth closed
-Food enters mouth-inhibits jaw muscles
-Jaw dropping relieves pressure of food-contract
-Pressure from food restored-inhibited |
|
|
Term
|
Definition
Chewed food+saliva=bolus
Tongue moves bolus to pharynx
Initiates swallowing reflex
Integration center=swallowing center of medulla oblongata |
|
|
Term
|
Definition
Functions
-Mix chyme
-Regulate gastric emptying
Mechanism
-Peristalsis
-Coordinated by enteric nervous system |
|
|
Term
| Gastric motility patterns |
|
Definition
Waves of peristalis(against closed sphincter)
-Upper body->pylorus
-Strengthen as approach pylorus
Functions in mixing of chyme
-Pyloric sphincter closed
Strength and pressure build up which then opens up sphincter
Functions in gastric emptying
-Stronger contractions cause pyloric sphinter to open
Emptying rate increases in proportion to
-Volume of chyme in stomach
-Strenght of gastric peristalsis |
|
|
Term
| Regulation of gastric motility |
|
Definition
Regulate force of contractions
Increase force
-Gastrin
Decrease force
-CCK
-Secretin
-GIP |
|
|
Term
| Motility of small intestine |
|
Definition
Purpose: mix and propel
Segmentation
-Mixes
Peristalsis
-Propels |
|
|
Term
| Regulation of motility in small intestine |
|
Definition
Distension-increases motility
Autonomic nervous system
-Parsympathetic->excites
-Sympathetic->inhibits
Hormones-gastrin stimulates motility
If one of these is out of whack, we have either constipation or diarrhea |
|
|
Term
|
Definition
Purpose:mix and propel
Haustrations:mix
-Proximal colon
-Like segmentation, but slower
Mass movement
-Propels bolus(material) toward rectum
-Similar to peristalsis
-Contraction lasts longer than relaxation |
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