Presented By: Sam Lund, Donovan Parker, Tom Srebernak

1. Extract nutrients from food

2. Transform nutrients into useful formsEx. Oreo= Glucose (sugar)

3. Absorb nutrients and distribute them where they are needed

Ingestion: Intake of nutrients

Digestion: Breakdown of large particles into smaller ones

Absorption: Uptake of nutrient molecules

Defecation: Elimination of undigested residues

1. Intake- Breaks up food- Moves food through the GI tract (Peristalsis)- Mixes with digestive enzymes

2. Secretion- Release of enzymes and hormones for

chemical digestion and regulation

3. Membrane Transport- Absorption of nutrients from the tissues by

the blood and lymph for transport

Mechanical: Physical breakdown of food

Chemical: Digestive enzymes hydrolyze food particles to break larger molecules into smaller ones

Some nutrients are absorbed without digestion Vitamins, minerals, cholesterol, water

Oral Cavity Pharynx Esophagus Stomach Small Intestine Large Intestine

6 meters in length

Functions: Chemical Digestion Nutrient Absorption Nutrient

Transportation

Digestion and absorption of food

Digestive enzymes secreted by the pancreas Enter the small

intestine via the pancreatic duct.

Duodenum (25 cm) Food mixes with bile

from the gallbladder. Jejunum (2.5m)

Absorbs nutrients into the bloodstream.

Ileum (3.6 m) Reabsorbs bile acids.

1.5 meters long Responsible for absorption of water from

the indigestible residue of food

Ascending Colon: Descending Colon:

Up the right side Down the left side

Cecum: Sac on Sigmoid Colon:

lower right side S-shaped

Ascending Colon-Removes water and other nutrients

Transverse Colon-Expulsion of waste materials, continues leaching out

Descending Colon-Absorbs water from fecal matter. Stores food particles that are to be emptied into the rectum.

Sigmoid Colon- Make and eliminate feces. Contains 60 varieties of bacteria

Rectum- Temporary storage for fecal matter before it’s eliminated from the body through the anal canal.

Functions: A. Ingestion:

Cheeks lips and tongue mobilize food

B. Digestion: Mechanical

Mastication Chemical

3 salivary glands Digests some starches and fat

Purpose: Pharyngeal constrictors force food down during swallowing

Divided into 3 parts: Epipharynx Mesopharynx Hypopharynx

Straight Muscular tube about 1 foot long

Purpose: Muscular contraction moves food towards stomach

Muscular sac on the left side of the peritoneal cavity

Functions: Food storage Mechanical

digestion Chemical

digestion

Saliva: Amylase: Breaks down starch Lipase: Breaks down fats when it enters the

stomach

Stomach: HCL: Activates enzymes, breaks up foods Pepsin: Digests proteins Renin: Digests milk

Starches bloodstream

Fats lymph vessels (lacteals)

Proteins bloodstream