Chapter 9- Digestion Flashcards
what are the 6 basic functions of the digestive system?
- ingestion of food and water
- mechanical digestion of food
- chemical digestion of food
- movement of food along the alimentary canal
- absorption of digested food and water into the blood and lymph
- elimination of material that is not absorbed
what is the function of the digestive system?
to extract nutrients from the food we consume, transport them via blood to cells and then absorbed by cells for use in chemical reactions
what happens at the mouth?
intake of food (ingestion)- the action of the jaw and teeth begins mechanical digestion where food is broken up into smaller pieces
what are the 3 pairs of salivary glands?
parotid salivary (front of ear), sublingual salivary (under the tongue), submandibular salivary (deep in the mouth)
what kinds of teeth do we have and how many?
4 incisors, 2 canines, 4 premolars, 6 molars
what are the functions of incisors?
biting and cutting
what are the functions of canines?
tearing
what are the functions of premolars?
tear and crush food
what are the functions of molars?
crushing and grinding food
what is the function of the oesophagus?
pushes food from the mouth to the stomach by a wave of circular muscular contractions called peristalsis- the mucus prevents friction
what kind of muscle surrounds the oesophagus?
circular muscle
what is the stomach?
a muscular organ located on the left side of the upper abdomen- it secretes acid and enzymes that digest food
how is mechanical digestion achieved in the stomach wall?
waves of muscular contraction that move along the stomach wall- the muscle has an oblique muscle layer as well as a circular and longitudinal layer
what is the thick, soapy liquid the stomach converts food into called?
chyme
what is mucosa?
the lining of the stomach
what is gastric juice?
a digestive juice that is responsible for chemical digestion in the stomach
what is the thick, circular muscle that results in constriction?
pyloric sphincter
what is the small intestine?
the longest part of the alimentary canal; receives material from the stomach (6m long)
what is the first part of the small intestine called?
duodenum