Dr kellys digestion Flashcards
one example of essential breakdown by digestion
Linoleic acid converted by enzyme fatty acid desaturase to g-linoleic acid, an essential precursor for
phospholipids and prostaglandins
Mammalian accessory glands
Are the salivary
glands, the pancreas, the liver, and the
gallbladder
what does saliva contain?
Saliva (exocrine secretion from salivary glands) contains mucus, a viscous mixture of water, salts, cells, and
glycoproteins, and amylase, which breaks down starch
pharynx
Is the junction that opens to both the esophagus and the trachea
Swallowing causes the which part of the body to block entry to the trachea, and the bolus is guided by the larynx, the
upper part of the respiratory tract
Epiglottis
what causes peristalsis?
Valves called sphincters
regulate the movement of
material between
compartments
what two names should I remember for the GI tract?
Serosa,
Submucosa
Chyme
The mixture of ingested food and gastric juice.
gastric juice is made form what?
-is made up of hydrochloric acid (HCl) and pepsin (a
protease that breaks peptide bonds to cleave
proteins into smaller peptides)
what produces the ions separately?
Parietal cells secrete hydrogen and chloride ions
separately into the lumen (cavity) of the stomach
what cells secrete inactive pepsinogen
Chief cells
Cell division adds a new epithelial layer every how many days?
three days
Gastric ulcers, lesions in the lining, are caused mainly caused by what bacteria?
Helicobacter pylori
what converts pepsinogen
to pepsin
HCl
where does most enzymatic hydrolysis of macromolecules
from food occur?
The small intestine
what happens in the duodenum?
Here, chyme from the stomach mixes with
digestive juices from the pancreas, liver,
gallbladder, and the small intestine itself
the pancrease produces what?
Trypsin and
chymotrypsin, which are activated in the
lumen of the duodenum for neutralising acidic chyme
what digests fats?
Bile salts, Bile also destroys nonfunctional red blood cells
what vein carries
nutrient-rich blood from
capillaries of the villi to
the liver, then to the heart
and onwards to all organs
the hepatic portal vein
How does bile break up fat molecules?
Bile salts break
up fat globules,
increasing
exposure of
triglycerides to
hydrolysis.
The enzyme
lipase breaks
triglycerides
down to fatty
acids and
monoglycerides.
After monoglycerides?-
Monoglycerides
and fatty acids
diffuse into
epithelial cells and
are re-formed into
triglycerides.,
Triglycerides
are incorporated
into water-soluble
particles called
chylomicrons
Chylomicrons
enter lacteals and
are carried away
by lymph.
The alimentary canal ends with the (3)
includes the colon, caecum, and rectum
The cecum aids what?
The fermentation of plant material
and connects where the small and large
intestines meet
the appendix does what?
appendix plays a minor role in immunity