3.4 Physiology of the GI Tract Flashcards
What are the four main roles of the digestive system?
ingestion
digestion
absorption
defecation
What is ingestion?
when food enters the mouth
What is digestion?
breakdown of food
What are the two parts of digestions?
mechanical
chemical
What is mechanical digestion?
food is physically broken down into smaller pieces
What are examples of mechanical digestion?
teeth chew food
stomach churns and mixes food
food is squeezed in the GI tract
What is chemical digestion of food?
chemical breakdown by enzymes into smaller nutrients
What is absorption?
the process of moving digested food into the bloodstream
What is defecation?
excretion of undigestible food from the anus
What type of digestion occurs in the mouth?
mechanical
chemical
What are the salivary glands?
parotid
sublingual
submandibular
What does chemical breakdown of starches in the mouth?
salivary amylase
What accomplishes mechanical digestion in the mouth?
tongue
teeth
What is peristalsis?
rhythmic muscular contractions
Does digestion occur in the esophagus?
no
