Chapter 25: Metabolism and Nutrition

Metabolism

Refers to all chemical reactions occurring in the body.

Catabolism

Break down complex molecules.

Exergonic

Produce more energy than they consume.

Anabolism

Combine simple molecules into complex ones.

Endergonic

Consume more energy than they produce.

Oxidation

Removal of electrons.

Dehydrogenation

Removal of hydrogens; liberated hydrogen transferred by coenzymes.

Nicotinamide adenine dinucleotide (NAD)

Obtained from Vitamin B.

Flavin adenine dinucleotide (FAD)

A coenzyme involved in redox reactions.

Reduction

Addition of electrons.

Substrate-level phosphorylation

Transferring high-energy phosphate group from an intermediate, the substrate directly to ADP.

Oxidative phosphorylation

Remove electrons and pass them through electron transport chain to oxygen.

Photophosphorylation

Only in chlorophyll-containing plant cells.

GluT (Glucose Transporters)

Bring glucose into the cell via facilitated diffusion.

Insulin

Causes insertion of more glucose transporters, increasing rate of entry into cells.

Glycolysis

Takes place in the cytosol; splits 6-carbon glucose into two 3-carbon molecules of pyruvic acid.

Anaerobic respiration

Does not require oxygen.

Aerobic respiration

Requires oxygen.

Glycogenesis

Making of glycogen, stimulated by Insulin.

Glycogenolysis

Catabolic process stimulated by Epinephrine that splits glycogen into glucose.

Electron Transport Chain

Series of electron carriers in inner mitochondrial membrane reduced and oxidized.

Chemiosmosis

Process where energy released from electrons is used to form ATP.

Heat loss methods

Conduction, convection, radiation, and evaporation.

Nutrition

Nutrients are chemical substances in food that body cells use for growth, maintenance, and repair.

Essential nutrients

Must be obtained from the diet.

Provitamins

Building blocks of vitamins.

Guidelines for healthy eating

Eat a variety of foods, maintain a healthy weight, choose foods low in fat, eat plenty of vegetables, fruits, and grain products.