Digestive System

Function of digestive system

Break down food, absorb nutrients, eliminate solid wastes

Mastication

Mechanical digestion. chewing

Peristalsis

Mechanical digestion. Contractions of digestive tract to push food along

Chemical digestion

Chemically change composition of food. Involves enzymes and secretions

Alimentary Canal / Gastrointestinal tract (purpose and path)

Muscular tube that pushes food through. (Oral cavity, pharynx, esophagus, stomach, small intestine, large intestine, anal canal)

Accessory organs

Aid in digestion. Produce enzymes and secretions

Mouth

Starts mechanical digestion and chemical digestion of starches. Salivary amylase breaks down starch

Pharynx / esophagus

passageway (peristalsis)

Stomach

Continues mechanical digestion and starts chemical digestion of proteins. Hydrochloric acid (HCL). Pepsin breaks down proteins

Small intestine

Chemical digestion of proteins, sugars, starches, lipids. Absorbs nutrients into bloodstream with capillaries. Liver and pancreatic enzymes act here

Large intestine

Reabsorbs water, forms feces, bacteria produces vitamin K. AKA colon.

Anal canal

elimination (poop out) feces

Salivary glands

Accessory organ. Produces saliva for lubrication and breakdown of starch.

Liver

Accessory organ. Produces bile (breaks down fat)

Gall bladder

Accessory organ. Stores bile

Pancreas

Produces enzymes that break down carbs, lipids, and proteins

Fetal digestion

All digested nutrients from placenta. Nutrients from blood through umbilical vein. Bypasses liver through ductus venosus

Purpose of epiglottis?

Blocks windpipe (trachea) to prevent food from going down it