Digestion system

Mouth/Oral cavity

Mechanical and chemical digest food

Example of mechanical digestion

Teeth chewing

Example of chemical digestion

saliva with amylase

Amylase

Break down carbs

Pharynx

back of throat
shares with air and food

Esophagus

sends bolus to stomach using peristalsis

throat

peristalsis

Muscle contractions

Epiglotties

cartilage flap that blocks food from entering trachea

Stomach

gastric acid is produced

behind rib cage

holds 2L

break down cells

HCl can

dissolve food, kill bacteria, pH for pepsin

interior surface of stomach lined with

pits leading to tubular gastric glands

3 types of cells in tubular gastric glands

mucous, parietal, chief

Mucous cells

releases mucus

parietal cells

releases HCl

chief cells

releases pepsinogen

pepsinogen

inactive form of pepsin

Stomach has both

Mechanical and chemical digestion

Example of mechanical and chemical digestion in stomach

enzyme pepsin and muscle movement

pepsin

enzyme that breaks down proteins in stomach

mucus coating

protects stomach from stomach acids

without mucus coating

get ulcers

chyme

food and acid

salivary gland

in mouth

releases saliva and amylase

liver

produces bile

filter blood of toxins

bile

emulsifies fats

gall bladder

stores and concentrates bile

pancrease

produces digestive enzymes

neutralizes acid when coming out of stomach into small intestine

trypsin digests

proteins in duodenum

lipase digests

lipids

amylase digests

carbs

nuclease digests

nucleic acids

trypsin, lipase, nuclease, amylase

work in duodenum

emulsification

separating fats into smaller droplets

Polysaccharides get broken down by

pancreatic amylase

polypeptide get broken down by

trypsin and chymotrypsin

DNA+RNA get broken down by

nucleases

Fat globules get broken down by

bile salts

Disaccharides get broken down by

Maltase, surcase, lactase, etc

smaller polypeptides get broken down by

various peptidases

Nucleotides get broken down by

other enzymes

fat droplets get broken down by

lipase

bile duct

carries bile from gallbladder to duodenum

pancreatic duct

carries pancreas solutions to duodenum

duodenum

first part of small intestine

most chemical digestion occurs

jejunum

second part of small intestine

ileum

final part of small intestine

small intestine

chemical digestion complete

absorption of food into blood stream

villi line the inside

villi

increase surface area to absorb more nutrients

large intestine/colon

place where water is removed

bacteria live here make vitamins

three parts of colon

asending, transverse, desending

cecum

small part between small intestine and large intestine

appendix

small extrusion from cecum

appendicitis

bacteria infection of appendix

rectum

stores waste

anus

exit for waste

heart burn

acid reflex from stomach into esophagus

function of digestive system

ingestion/eat

digestion/break food into monomers

absorption of nutrience

elimination of solid waste