The Digestive System - Section 30.3

List the structures that food travels through during digestion and give the function of each -

1. Ingestion- Getting food in the system. Process of taking food into digestive system. 2. Digestion- Food passes through the digestive system, breaking food down into smaller parts. 3. Absorption- Absorbed by cells in the small intestine. Moving nutrients, water, and vitamins into blood to be delivered to cells. 4. Elimination- Cannot digest and absorb all substances in food that enter the body. Cellulose travels through large intestine. Remove wastes from body.

Peristalsis

Contractions of smooth muscles that provide the force that moves food through the esophagus to the stomach.

Amylase

Enzyme in saliva that breaks the chemical bonds n starches.

Pepsin

Enzymes that break down proteins into smaller polypeptide fragments.

Villus

Finger-like projection in the small intestine that aid in the absorption of nutrient molecules.

list the steps of the food digestion in humans -

Ingestion, Digestion, Absorption, and Elimination

Describe the function at each step of food digestion in humans -

Ingestion- Process of taking food into digestive tract. Digestion- Breaking food down into smaller parts. (Mechanical digestion breaks down large pieces of food, to smaller pieces. --- Chemical digestion enzymes break down food into the small molecules the body can use.) Absorption- Moving nutrients, water, and vitamins into blood to be delivered to cells. Elimination- Removing wastes from body.

Chyme

Mixture of enzymes and partially-digested food.

Describe the absorption of food nutrients during the digestive system -

Most nutrients from food are absorbed through the walls of the small intestine. The large intestine absorbs water and several vitamins and prepares waster for elimination from the body.

Explain how nutrients are absorbed. Include an explanation of villi -

Nutrients are absorbs by being found on the walls of the small intestine. Villi plays a part in this because they are finger-like projections that increase surface area for absorption of nutrients into the blood.

Describe the functions of the digestive system -

The digestive system converts food into small molecules that can be used by the cells of the body. Food is processed by the digestive system in four phases.

Explain the function of the digestive system -

The function of the digestive system converts food into smaller molecules. It can be used by the cells of the body.