stomach/small intestine quiz

functions of stomach

1) temporary storage of ingested food, 2) mechanically breaking down food (into chyme), 3) chemically breaking down food (enzymes and acid), 4) production of intrinsic factor (binds with B12 to be absorbed by intestines)

functions of b12

helps with blood cell formation, nerve tissue health, and brain function

lack of b12

anemia, nervous and brain issues

cardia

closest to the heart, connects to the esophagus

cardiac sphincter

closes off the top of the stomach

fundus

“hump” on top of stomach region

body

shaped like the letter C, biggest region in the stomach

pylorus

towards the bottom of the stomach

pyloric sphincter

controls the exit of chyme from the stomach into the intestines

rugae

ridges in the stomach, flat when empty expands when filled

1-1.5 liters

how many liters of food can the expanded rugae hold?

3 layers of muscularis externa

what’s the main difference between the stomach and other things?

it allows for churning action in the stomach

what does the extra layer of muscularis externa do in the stomach?

lesser omentum

on the medial side of the stomach (lesser curvature), attaches the stomach to the liver

greater omentum

on the lateral side of the stomach (greater curvature), hangs and attaches to the large intestine

fundus,body

parietal cells location

parietal cells

in stomach- secretes HCl and intrinsic factor that helps the intestines absorb B12

chief cells

in stomach- produces pepsinogen (which meets HCl and becomes the active pepsin that digests proteins)

fundus, body

chief cells location

mucosal epithelium

goblet cells location

goblet cells

produces alkaline mucus to protect stomach lining, reproduces every 1-2 days

pylorus

endocrine (G-cells) location

endocrine cells (G-cells)

produces gastrin, enhances mucosal growth, gastric motility, secretes HCl in the stomach

gastritis

inflammation of stomach lining

ulcers

erosion of stomach lining, peptic ulcers caused by H. Pylori bacteria, chances of it increase with aspirin, ibuprofen, smoking, drinking, etc.

cephalic, gastric, intestinal

three phases of gastric activity

cephalic phase

CNS prepares the stomach to receive food, anticipating food increases gastrin production

gastric phase

begins when food enters the stomach, stretching of stomach increases gastrin production

intestinal phase

controls the pace of gastric emptying, decreases gastrin production and activity

duodenum

first part of small intestine, 10 in-1 ft long

jejunum

second part of small intestine, 8 ft long

iluem

third part of small intestine, 12 ft long

ileocecal valve/sphincter

marks a junction with the ileum and large intestine

21 ft, 1.5-1 in

how long is the small intestine? what diameter is the small intestine?

duodenum, jejunum, ileum (dj I)

three parts of the small intestine (in order)?

plicae

transverse folds in the mucosa

villi

small projections on the plicae

adds surface area, increases absorption

why does the villi, microvilli, and plicae need to be there?

lacteal

a lymphatic capillary that absorbs large fat droplets

peristalsis

small-scale periodic contractions of the muscularis externa

gastroenteric reflex

due to stretch receptors in the duodenum that inhibits gastric emptying/activity as well as increase glandular secretions and peristalsis in the small intestine

gastrocolic (gastroileal) reflex

due to stretch receptors in the stomach that stimulates opening the ileocecal valve and increase large intestine contractions

1\.8 liters

how much intestinal juice is secreted a day?

intestinal juice functions

1) moistens chyme, 2) buffers stomach acid, 3) dissolves products of digestion

intestinal gastrin

stimulates production of acid and enzymes in stomach

if chyme has a lot of undigested proteins

when is gastrin released in the small intestine?

low pH

when is secretin released in the small intestine?

secretin

decrease stomach secretion/movement, stimulates secretion of bile from liver/gallbladder, stimulates sodium bicarbonate from pancreas (both neutralize stomach acid)

if chyme has fats and partially digested proteins

when is CCK released in the small intestine?

cholecystokinin (CCK)

stimulates liver to make bile and gallbladder to release bile in duodenum, reduces hunger feeling, decreases stomach secretion/movement

if chyme has large amounts of glucose

when is GIP released in the small intestine?

gastric inhibitory peptide (GIP)

stimulates pancreas to release insulin, decreases stomach secretions/movement

duodenum

where does the most enzymatic digestion occur?

jejunum

where does the most absorption occur?

gallbladder, liver, pancreas

where are the enzymes and buffers released from?

hepatopancreatic sphincter

the pancreatic duct that enters the duodenum

pancreatic acini

endocrine cells location

common bile duct

where bile makes its way to the duodenum

1000

how many ml of secretions are in the pancreas

insulin, glucagon

endocrine secretions that control the blood sugar level/pressure

carbohydrases

digestive exocrine secretions that work on sugars and starches

lipases

digestive exocrine secretions that work on lipids

proteases

digestive exocrine secretions that work on proteins

nucleases

digestive exocrine secretions that work on nucleic acids

secretin, and CCK

chyme releases hormones, which release pancreatic juices

secretin

triggers water and sodium bicarbonate release

when the chyme has a low pH

when in secretin released in the chyme?

when lipids and proteins are in the chyme

when in secretin released in the chyme?

CCK

triggers enzyme release

right, left, caudate, quadrate

what is the four quadrants of the liver?

right

largest quadrant of the liver

liver lobule

basic functional unit of the liver

hepatic artery

where does the liver get its blood supply?

bile canaliculi

what carries bile to bile ducts?

cystic duct

what carries bile to be stored in the galbladder?

produce bile, metabolic regulation, hematological regulation

three functions of the liver

metabolic regulations

trait in which the liver stores nutrients like glucose and glycogen, and vitamins A, D, K, and E. releases nutrients when needed.

hematological regulation

trait in the liver in charge of plasma protein regulation, removing old RBC’s and toxins

galbladder functions

stores and concentrates bile to release into duodenum

bile can enter the small intestine

what happens when the hepatopancreatic sphincter is relaxed?

CCK

what hormone is used to relax the hepatopancreatic sphincter

produces bile

what is the function of the liver?

emulsifier

it breaks down big fat droplets into smaller particles so they can be digested more efficiently aka bile

ileocecal valve

where does the large intestine start?

anus

where does the large intestine end?

5 ft, 3 in

how long is the large intestine? what’s the diameter

10 in-1 ft

how long is the duodenum?

8 ft

how long is the jejunum?

12 ft

how long is the ileum?

absorb vitamins, get rid of waste products, temporary feces storage

what are he 3 main functions of the large intestine?

cecum, colon, rectum

three parts of the large intestine?

ascending, transverse, descending, sigmoid

four parts of the colon?

appendicitis

when your appendix is filled with pus and infected

haustra

what are the pouches on the large intestine know as? they help with distension and elongation

anus

end of the digestive tract?

external

what is the voluntary anal sphincter (smooth muscle)

internal

what is the involuntary anal sphincter (skeletal muscle)

beta cells

produces insulin

alpha cells

produces glucagon

alpha and beta cells

two main cells in the pancreas?