Digestive systems

Life Process?

NutritionTransport

When is food “in you”?

Autotrophic vs. heterotrophic

Eat other things for fuel

Raw materials for synthesis and assimilation

Human Digestive System

Bringing food close and broken down enough to be absorbed.

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?