Nutrition 1020

The breaking down of food.

• Big food parts into smaller ones (mechanical)
• – Involves muscles and nerves

• Big nutrients into smaller ones (chemical)
• – Involves acid, enzymes, and hormones

Protein that catalyze metabolic reactions,and are necessary for most biochemical reactions to occur.

Examples include: amylase for carbohydrate, protease for protein, and lipase for Lipids/Fat.

food substances.

Examples include: amylase for carbohydrate, protease for protein, and lipase for Lipids/Fat.

Chemicals produced by cells (typically in an endocrine gland), and are secreted, then affect the behavior of cells at distal sites in the body.

Examples of hormones indigestion include:cholecystokinin and secretin.

chewing (mastication)

saliva(lubrication) and amylase (breaks down digestible carbohydrate)

ball of food in the esophagus

muscular wave action that occurs throughout the intestinal tract. It is controlled by the central nervous system and facilitates excretion by propelling food stuff through the body.

Peristalsis begins.

muscular organ & storage reservoir.

• Mechanically digests food by mixing & churning.

• Chemically digests food with acid and some enzymes (pepsin).

• Here, the bolus becomes chyme.

Sites of Absorption:

Duodenum: many nutrients

Jejunum: Many nutrients

Colon (large Intestine): water

Ileum: only a selected nutrients

for assistance in digesting the food stuff.

By hormones.

- The cells of the intestinal wall produce the hormones cholecystokinin and secretin which enter the blood stream and signal the accessory organs.

• The Liver– Makes bile

• The Gallbladder– Stores bile

• The Pancreas

– Makes enzymes for the chemical digestion of carbohydrates, proteins,and fats

– Makes sodium bicarbonate to neutralize stomach acid

Emulsifier

Nutrients like water & lipid byproducts pass freely across membranes via a concentration gradient.

Nutrients like water soluble vitamins diffuse across membranes using a specific/selective transport proteins.

Nutrients like glucose & amino acids move across membranes against a concentration gradient using a specific/selective transport protein & energy/ATP.

• Blood vessels: water soluble nutrients

• Lymphatic vessels: fat soluble nutrients

• • Short term
• • Intermediate
• • Long term

Breaking down(things get smaller). Involve hydrolysis reactions. Are degrading or destructive in nature.

Building up (things get bigger). Involve condensation reactions.Are synthesizing or constructive in nature.

The balance of catabolic and anabolic reactions in a person so a relatively stable internal environment or equilibrium is achieved.

Water and water soluble waste.

Water and water soluble waste.

Carbon dioxide and water.

Water is removed and waste (bacteria, fiber, sloughed cells, and undigested food) is compacted.