Honors Biomedical Sciences Test 3

6 functions of digestive system

1. Chemical Digestion
-enables by enzymes which break down foods into smaller molecules

2. Absorption
-absorbs water and nutrients

3. Secretion
-secretes enzymes, bile, HCL, water

4. Mechanical Digestion
-mouth/teeth/tongue
-HCL
-increases surface area

5. Ingestion
-take in food

6. Excretion
-get rid of waste

3 parts of the small intestine

1. Duodenum
-25 centimeters
-secretion
-chemical digestion
-cells are simple cuboidal

2. Jejunum
-2.5 meters
-secretion to absorption
-cells are simple cuboidal to simple columnar

3. Ileum
-3.5 meters
-all absorption
-cells are simple columnar

5 pancreatic enzymes

1. Sodium Bicarbonate
-NaHCO3
-neutralizes acids
-baking soda

2. Trypsin
-breaks down proteins
-di/mono saccharides

3. Pancreatic amylase
-poly/di
-breaks down carbs

4. Lipace
-breaks down lipids

5. Nucleases
-breaks down nucleic acids

mesentery

-Structure that suspends the small intestine from the posterior body wall
-serosa that holds digestive organs in place

Fingerlike extensions of the intestinal mucosa that increase the surface area

villi

Peyer's patches

-removes bacteria before nutrients enter blood-stream
-collections of lymphatic tissue found in the submucosa of the small intestine

Folds of the small intestine wall

plicae circulares

Two regions involved in the physical breakdown of food

-stomach
-oral cavity

Organ that mixes food in the mouth

tongue

Food shoot with no digestive or absorptive role

Esophagus

Folds of the stomach mucosa

rugae

Saclike out pocketing of the large intestine wall

haustra

Projections of the plasma membrane of a cell that increases the cells surface area

microvilli

Prevents food from backing into the small intestine once it entered the large intestine

Ileocecal valve

Organ responsible for most food and water absorption

small intestine

Oregon primarily involved in water absorption in feces formation

Colon

Area between the teeth and the lips/cheeks

vestibule

Blind sack hanging from the initial part of the colon

appendix

Organ in which protein digestion begins

stomach

lesser omentum

-membrane attached to the lesser curvature of the stomach
-fat that holds stomach in place

Organ into which the stomach empties

small intestine

Sphincter that controls the movement of food from the stomach into the duodenum

pyloric valve

Uvula hangs from his posterior edge

Soft palate

Organ that receives pancreatic juices and bile

small intestine

Region through which feces are expelled from the body

Anal canal

inflamed blood vessels at anus

hemorrhoids

prevents food from backing up into stomach

pyloric sphincter

neutralizes acids entering small intestine

bicarbonate

maltase, sucrase, lactase

intestinal juices

portion of large intestine laying across abdomen

transverse colon

anterior roof of mouth

hard palate

sublingual gland

-salivary gland under tongue
-gleet
-3-5% of saliva

frenulum

-secures tongue to floor of mouth
-holds tongue together

partially digested food in the stomach

chyme

mainly water, bacteria, and undigested food

feces

allows you to release feces

???

partially digested food in mouth

bolis

lacteal

-suck up fats

entrance in small intestine for pancreatic juices and bile

hepatopancreatic sphincter

entrance in large intestine from small intestine

ileocecal valve

breaks down nucleic acids

nucleases

holds stomach in place

greater omentum

lymphatic system in place when you swallow

tonsils

space between teeth and gums

vestibule

pockets in large intestine

haustra

secretes HCL

parietal cells

first part of small intestine

duodenum

deep folds in small intestine

plicae circulares

secretes pepsinogen

chief cells

uvula

-prevents food from entering nasal cavity
-punching bag

breaks down lipids

lipase

secretes bile

liver

folds in stomach

rugae

fingerlike projections in small intestine

villi

serosa that holds digestive organs in place

mesentery

food tube

esophagus

goblet cells

-secretes mucous
-protects lining

bile

-emulsifies fats
-breaks it down mechanically

enzyme that breaks down starch in mouth

amylase

breaks down proteins

trypsin

terminal part of small intestine with major absorption of nutrients

ileum

stores bile

gall bladder

prevents food from reentering esophagus

cardio esophageal sphincter

muscular contraction that moves food

peristalsis

submandibular gland

-thick
-located under the jaw
-70% of saliva

epiglottis

-prevents food from entering trachea

adenoids

name for 3 tonsils

how long is food in stomach

3-6 hours

how much food can stomach hold

1-1.5 Liters

function of lesser and greater omentum

fat that holds stomach in place

ulcer

hole in lining of stomach

3 cells in gastric pits

-cheif cells
-parietal cells
-goblet cells

pepsin

-from chief cells and parietal cells
-peptide bonds which are combination of proteins

intestinal juices

1. peptidase
-breaks down amino acids

2. lipase
-breaks down lipids into fatty acids and carboxyl

3. sucrase, maltase, lactase
-break down di into mono

main function of large intestine

-reabsorb water
-if you don't absorb it, get diarrhea

feces

-dead cells
-cellulose

internal sphincter

-tells you you have to go
-involuntary (uncontrollable)

external sphincter

-tells you no, wait
-voluntary (controllable)

taenia coli

strip of muscle throughout large intestine that helps get feces out

masseter

helps bite down

pylorus region and cardiac region

-in stomach
-pylorus: acidic
-cardiac: not acidic

capilarries

-collect blood and water
-absportion part of sm. int

brush border

-on microvilli
-creates more surface area

how much intestinal juice

1.8 L

3 tonsils

-pharyngeal
-palatine
-lingual

auditory canal

goes to the ear