Digestive systems Life Process? Nutritio n Transpor t When is food “in you”? Autotrophic vs. heterotrophic Eat other things for fuel Raw materials for synthesis and assimilation
Jan 03, 2016
Digestive systems
Life Process?
NutritionTransport
When is food “in you”?
Autotrophic vs. heterotrophic
Eat other things for fuel
Raw materials for synthesis and assimilation
Two categories of organs
• Alimentary canal AKA digestive tract AKA GI tract
– “Food tube”; food passes through these organs
• Accessory organs
– Add digestive juices to food.
AlimentaryMouth: Put food in here
Pharynx: Throat
Esophagus (5): Peristalsis (squeezing food through the tube) begins. Brings food to stomach.
AccessoryTeeth (1) : Chew food ->
increases surface area of food for enzyme action
Tongue (2) : Tastes. Is this food?
Salivary glands (3) : Produce saliva: enzymes and lube
Epiglottis (4) : Closes trachea (windpipe) during swallowing
AlimentaryStomach (7/14): Food is
ground into a paste. Protein digestion begins
AccessoryLiver (6/17) : Produces bile:
breaks fat into smaller blobs (emulsifies)
Gall bladder (16) : Stores up bile for fatty meals
Pancreas (8/15) : Produces other digestive enzymes
AlimentarySmall intestine (10):
Digestion completes and most absorption of nutrients. Has adaptation for increased surface area (more absorption)
Large intestine (9):Water absorption
Rectum (12): Storage of feces
Anus (13): Muscle that holds it in/lets it out
AccessoryAppendix (11) : Helps
control gut bacteria populations?