UNIT 1 MODULE 2 Flashcards
What are the major functions of the digestive system?
- break down incoming nutrients to be transported to cells of the body
2.supply cells with water - remove undigested waste material
What are the two forms of digestion?
- Mechanical Digestion
-physically breaking down food to increase its surface area
-mouth and stomach - Chemical Digestion
-break down nutrient molecules using enzymes to harvest energy
-small intestine
MOUTH (Digestive tract organ)
breaks up food by mechanical/chemical digestion
ESOPHAGUS (Digestive tract organ)
transports food to stomach
STOMACH (Digestive tract organ)
mechanical mixing of food
SMALL INTESTINE (Digestive tract organ)
major organ of digestion and absorption
LARGE INTESTINE (Digestive tract organ)
eliminates indigestible materials, reabsorbs water
SALIVARY GLANDS (Accessory Organs)
lubricates food ad provides enzymes
LIVER (Accessory Organs)
produces bile, processes and stores nutrients
PANCREAS (Accessory Organs)
produces digestive enzymes for the small intestine, regulates blood sugar levels
GALLBLADDER (Accessory Organs)
stores bile
How does the structure of the small intestine inform its function?
the lining is highly specialized for maximizing digestion and absorption of nutrients.
What features are
present on the small intestine that help it do its job?
Folds, Villi: increase surface area to maximize nutrient absorption
Capillaries: inside villi connect small intestine to circulatory system
Lacteals: inside villi transport fat-soluble molecules to lymphatic system
What are enzymes?
metabolic catalyst that speed up chemical reactions or allow them to occur at all
How do enzymes work?
- Substrate (nutrient) binds to activate site of enzyme
- enzyme changes shape, which changes shape of nutrient molecule
- once reaction is complete, nutrient unbinds from enzyme