chp 9 digestion

function is to break down macromolecules found in food particles small enough to cross plasma membranes

digestive system

carbs are broken down into???

monosaccharides

proteins are broken down into??

amino acids

fats are broken down into???

fatty acids and glycerol

what is alimentary
canal: long, muscular tube from mouth to
anus: —— is for ingestion, digestion,
absorption, elimination

gastrointestinal tract

the  mouth, pharynx,
esophagus, stomach, small intestine, large
intestine, rectum, anus are all what type of organs 

digestive organs

the salivary glands, liver,
gallbladder, pancreas are what type of organs 

accessory organs 

what is intake of food via the mouth

ingestion

what is mechanically or chemically breaking down foods into their subunits

digestion

what is digestion breaks down food via physical means

mechanical digestion

what is digestion breaks down food via enzymes

chemical digestion

what is food must be moved along the GIT in order to fulfill all functions

movement

what is movement of nutrients across the GIT wall to be delivered to cells via the blood

absorption

what is removal of indigestible molecules

elimination

what

-Houses salivary glands, teeth, and tongue
• Site where mechanical digestion by force and
chemical digestion by enzyme begin

mouth

what

• Produce saliva, which moistens food
(to be able to taste it and swallow it)
and contains salivary amylase (digests
carbs)

salivary glands 

what is

-Food manipulation (mechanical
digestion)
• Skeletal muscle.

tongue 

what are used for mechanical breakdown of food

teeth

what

– Stimulates involuntary swallowing
reflex when food is present
– Food, liquid, air pass

pharynx

what

– Moves food(bolus) from the pharynx to the
stomach via peristalsis contractions that push
food through the digestive tract

esophagus

what is

– a ring of muscle that acts as a
valve

sphincter

what is a 
constriction between esophagus and
stomach; controls flow of food into stomach

Lower gastroesophageal sphincter

what

• Fn: to store food and start digestion of proteins
• Mixes food with stomach secretions, forming
chyme(kaim: a mixture of food and stomach
secretions)

stomach

what

-WHAT activates pepsin to digest proteins
-WHAT also kills pathogens: pH of 2
-Thick mucus protects stomach lining from WHAT 

HCI

what

failure of the lower
gastroesophageal sphincter; the lining
of the esophagus is thinner than the lining
of the stomach; if the regurgitation of
chyme enters the esophagus, it produces
a burning sensation

heartburn

what
caused by bacteria and pain relievers
- possibly causing perforation in tissues

peptic ulcer

what

• Fns: the primary site of chemical digestion
and nutrient absorption
• Three regions: duodenum, jejunum, ileum
• Bile emulsifies fats=emulsification
-Mechanical digestion; breaks up fat globules
-Lipase by the pancreas breaks fats down into
glycerol and fatty acids

small intestine

the small intestine the following major digestive
enzymes produced by the pancreas,
secreted into the WHAT 

duodenum

pancreatic amylase digests what

carbs

trypsin digests what 

proteins

lipase digests what

lipids

nuclease digests what

nucleic acid

what in the small intestine increase surface area for absorption

villi

what is the small intestine enzyme that digest lactose

lactase

what

- Secretes pancreatic juice
- contains digestive enzymes

pancreas

what

– Nutrient-rich blood from intestines travels to
the liver via the hepatic portal vein: pic
– Detoxifies the blood
– Produces bile
– Produces plasma proteins
– Involved in blood glucose homeostasis
• Stores glucose as glycogen; when blood glucose is
low, it releases glucose by breaking down
glycogen

liver

what

- Just below the liver
- Stores and concentrates bile and releases
bile into the small intestine
- Bile is rich in cholesterol; can crystallize and
form gallstones

gallbladder

what disease?

viral infection of the liver;
attacks and destroys liver cells

hepatitis

what disease ?

– Often seen in alcoholics due to malnutrition
and the excessive alcohol (a toxin) the liver is
forced to break down
– The liver can regenerate and recover if the
rate of regeneration exceeds the rate of
damage

cirrhosis

functions of what

– Does not produce digestive enzymes
– Absorbs water from feces to prevent
dehydration
– Absorbs vitamins produced by bacteria in the
____

large intestine

what is

¾ water, ¼ solid wastes:
bacteria, dietary fiber, indigestible
materials

– Bacteria break down indigestible material (like
cellulose) and produce vitamins(K and B);
also give off gas
– Odor of feces, gas comes from bacteria
– Color comes from bilirubin- the yellowish bile
pigment produced from breakdown of
Hemoglobin, secretes it in bile.

feces

what anal sphincter is

is involuntary, smooth
muscle

internal sphincter

what anal sphincter is 

is skeletal muscle;
we learn to control it at two or three
years old

external sphincter

what disease 

- small growths in the colon lining
– Can be benign or cancerous
– If colon cancer is detected while still confined
to a polyp, the expected outcome is a
complete cure
– Increased dietary fat raises the risk of colon
cancer
– Dietary fiber prevents colon cancer, and
regular elimination reduces the time that the
colon wall is exposed to cancer-promoting
agents in feces

polyps