Nutrition (A+P II)

Nutrition

The study of how organisms obtain and utilize the nutrients that they need to grow and sustain life

Nutrients

Most biological molecules that the body needs for development and growth, maintenance of anatomic structures and physiologic, and repair of damaged tissues

Essential nutrients

Must be obtained and absorbed by processes of the digestive system

Nonessential nutrients

Can be provided by biochemical processes within the body so are not required to be part of the dietary intake

Macronutrients

Provide fuel for the processes of cellular respiration to form ATP

Macronutrients are

Carbohydrates, lipids, and proteins

Calories

Amount of heat required to raise the temperature of 1 gram of H2O by 1 degree Celsius

Carbohydrates

Monosaccharides, disaccharides, or polysaccharides

Monosaccharides

Glucose, fructose, galactose

Dusaccharides

Sucrose, lactose, maltose

Starch

Polysaccharide polymer of glucose found in potatoes, carrots, bananas, grains, beans, peas, breads, pasta

Fiber

Cellulose that cannot be digested and absorbed by GI tract, remains within the lumen of GI tract and adds bulk

Lipids

Hydrophobic molecules: include triglycerides, phospholipids, steroids

Triglyceride

Primary nutrient supplying energy to cells, necessary for absorption of fat-soluble vitamins

Cholesterol

Requirement as a component of plasma membrane, precursor molecule for formation of steroid hormones, bile salts, vitamin D, comes from diet or is synthesized by liver

Protiens

Synthesized from 20 different amino acids, adequate dietary intake provides amino acids to synthesize new proteins

8 essential amino acids

Isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine

Builds skeletal muscle

Leucine, isoleucine

Complete protiens

Contain all essential amino acids

Incomplete proteins

Do not contain all essential amino acids