OLI AP Unit 2 Module 3 Exchange with the Environment

digestive system and respiratory system

digestive system functions

ingest, break down, and absorb nutrients from food

eliminate wastes as feces

order of digestion

food - mechanical digestion - chemical digestion

digestive system main organs

mouth

pharynx

esophagus

stomach

small intestine

large intestine

anus

digestive system accessory organs

salivary glands

pancreas

liver

gall bladder

stomach

muscular sac

glands in stomach walls secrete enzymes and acids to break down food

muscles in stomach walls churn food and digestive juices together

small intestine

additional digestive juices made by pancreas, liver, and walls of small intestine continue digestion

large surface area for efficient absorption of nutrients into circulatory system

parts of small intestine

duodenum

jejunum

ileum

large intestine

excess water is reabsorbed

undigested portion of food leaves body

resident microbes/gut microbiota can digest substances that our cells cannot

parts of large intestine

cecum

colon

rectum

salivary glands

produce saliva which includes amylase

amylase

enzyme that breaks down carbohydrates

pancreas

secretes a variety of enzymes that break down fats, carbohydrates, and proteins, as well as bicarbonate ions that neutralize stomach acids

liver

makes bile which aids in fat digestion and absorption

gall bladder

stores and concentrates bile

secretes bile into small intestine

respiratory system function

exchange oxygen and carbon dioxide with environment

respiratory system organs

nose

mouth

pharynx

epiglottis

larynx

trachea

lungs

bronchi

bronchiole tree

alveoli