Anatomy and Physiology Quiz 3.3 (p. 43-47)

Carbohydrates

• also called sugars or starches

• the body’s main energy source

• always consists of carbon, hydrogen, and oxygen to form units called saccharides

Monosaccharides

one sugar unit (glucose)

Disaccharides

two sugar units (combinations of monosaccharides; sucrose)

Polysaccharides

many sugar units; AKA “complex carbohydrates”

Glycogen

stored form of glucose

Starch

how plants store polysaccharides (rice, potatoes, corn)

Cellulose

produced by plant cells to fortify their cell walls (humans cannot digest it)

Lipids (fats)

• composed of carbon, hydrogen, and oxygen

• reserve supply of energy, insulates nerves, vitamins, cushions organs

Triglycerides

• the most abundant lipid

• also called fats and can be classified as saturated or unsaturated

Saturated

• carbons are filled with hydrogen atoms; each carbon atom is bonded to the max number of hydrogens possible

• solids at room temperature

• derived from animals

Unsaturated

• carbon atoms are not saturated

• liquids at room temperature

• also called oils

• derived from plant sources

Steroid

• all types are made of cholesterol

  • helps make vitamin D

  • helps proper nerve function

• most is made in the liver

Phospholipids

forms the structure of cell membranes

Proteins

• the most abundant and important organic compounds in the body

• responsible for the structure and metabolic functions of cells

Keratin

provides strength to hair, skin, and nails

Collagen

provides structure to bones, cartilage, and teeth

Antibodies

defends against bacteria

Enzymes

catalysts for vital chemical reactions

Hemoglobin

carries oxygen in the blood

Hormones

chemical messengers to cells

Amino Acids

• smaller units that make up large molecules

• there are 20 different kinds; 11 of which are naturally made in the body

Nucleic acids

• Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA)

• consist of molecules called nucleotides

Nucleotides

made of a sugar, phosphate group, and nitrogen base

DNA

• the largest molecule in the body

• carries the genetic code for every inherited characteristic

• uses the sugar deoxyribose

RNA

a simpler strand of nucleotides that copies DNA’s genetic code to direct protein synthesis

ATP (Adenosine Triphosphate)

• stores the energy released from the breakdown of nutrients and then provides fuel for cellular reactions

• made of a base, sugar, and 3 phosphate groups

How ATP works:

1. The phosphates are connected by high-energy bonds

2. One of the bonds is broken through a reaction; energy (ATP) is released to do work

3. ATP becomes ADP (adenosine diphosphate) + a phosphate group

4. The cell uses some energy to reattach the third phosphate to ADP, turning it back into ATP