digestive system Flashcards
path of food
mouth –> pharynx –> esophagus –> stomach –> small intestine –> large intestine –> rectum –> anus
salivary glands
secrete saliva, which contains enzymes that initiate breakdown of carbohydrates
mouth
mechanical breakdown of food; begins chemical digestion of carbohydrates
pharynx
connects mouth with esophagus
esophagus
peristalsis pushes food to stomach
stomach
secretes acid and enzymes. Mixes food with secretions to begin enzymatic digestion of proteins
liver
- produces bile, which emulsifies fat
- Converts glucose in blood to glycogen and stores it
- changes toxins to a less toxic form
gallbladder
stores bile and introduces it into small intestine
pancreas
produces and secretes pancreatic juice, containing digestive enzymes and bicarbonate ions, into small intestine
small intestine
Mixes food with bile and pancreatic juice. Final enzymatic breakdown of food molecules; main site of nutrient absorbtion
large intestine
absorbs water and electrolytes to form feces
contains bacteria
made up of 3 parts
rectum
regulates elimination of feces
anus
butt/butthole
accessory organs
liver, salivary glands, pancreas, gallbladder
Mechanical digestion
the physical breakdown of food
ex. chewing in your mouth
stomach muscles breaks down food
Chemical Digestion
(enzymes)
when enzymes and gastric juices in different organs break down macromolecules so they can be absorbed by the body
Ex:Digestive enzymes-small intestine/mouth-saliva/stomach-gastric juices
location in digestive system
carbohydrates
starts in mouth, continues in stomach, finished in small intestine
enzyme produced in mouth = amylase
location in digestive system
Protein
starts in stomach and finished in small intestine enzymes = protease like pepsin, trypsin
location in digestive system
Fat/lipids
in the small intestine
enzyme = lipase
where does water reabsorbtion occur?
large intestine
function of the digestive system
- break down carbohydrates, lipids, and proteins in food into smaller molecules to give the body energy in a form it can use, ATP
- Absorb nutrients and water
- eliminate waste
the contraction of the esophagus muscles
Peristalsis
epiglottis
a flap which covers the trachea and keep food from going into our lungs.
In the stomach there is
acid, pepsinogen, and mucus
a. acid kills bacteria and breaks apart cells
b. pepsinogen and HCl produce pepsin. Pepsin is an enzyme that begins the chemical digestion of proteins
Mucus helps protect the walls of the stomach from the acidic juices, so it doesn’t digest itself.
juices + food = chyme
bile
made up bile salts which help to break down fats and absorb vitamins A, D, E and K.
carbs
amylase
fats
lipase
nucleic acids
nuclease
proteins
trypsin
pancreatic juices
contain base that neutralizes the chyme from the stomach
The walls of the small intestine fold up and down into finger-like projection called
villi
microvilli
Each villi is covered with these tiny projections that increase the surface area of the small intestine
rapidly absorb nutrients
effects of digestive enzymes
