Level 1: Chapter 20: Metabolism, Nutrition, and Body Temperature

Vocabulary flashcards covering key terms and definitions from Chapter 20: Metabolism, Nutrition, and Body Temperature.

Metabolism

The sum of all chemical processes in the body, including catabolic and anabolic reactions, that sustain life.

Catabolism

Breaks down complex compounds into simpler ones, releasing energy.

Anabolism

Builds simple compounds into larger, needed substances.

Cellular respiration

Process by which nutrients are oxidized to produce ATP in cells; includes glycolysis and aerobic pathways.

Glycolysis

Anaerobic phase of glucose catabolism; yields 2 ATP per glucose; end product is pyruvic acid.

Anaerobic respiration (glycolysis)

The glycolytic, oxygen-free portion of glucose catabolism that produces a small amount of ATP and pyruvic acid.

Aerobic respiration

Glucose catabolism in the presence of oxygen; yields about 32 ATP per glucose; end products are CO2 and H2O.

Pyruvic acid

End product of glycolysis; can enter aerobic pathways to produce more ATP.

Glucose

A simple sugar; the primary energy source for cells.

ATP

Adenosine triphosphate; the energy currency of cells produced during cellular respiration.

Glycogen

Stored form of glucose in liver and muscle; liver glycogen can release glucose into blood; muscle glycogen used by muscles.

Fatty acids

Building blocks of fats; oxidized in mitochondria to generate ATP; typically yield more ATP than carbohydrates.

Ketones (ketone bodies)

Partially metabolized fatty acids that can be used by the brain for energy.

Amino acids

Building blocks of proteins; categorized as essential (must be obtained from diet) and nonessential (can be synthesized by the body).

Deamination

Removal of an amino group from amino acids before oxidation; produces ammonia which is converted to urea.

Urea

Waste product formed from deamination; eliminated by the kidneys.

Essential amino acids

Nine amino acids that must be supplied by the diet; animal proteins typically provide all of them.

Nonessential amino acids

Eleven amino acids that can be synthesized by the body; some may be required under certain conditions.

Minerals

Inorganic elements required for various physiological processes (e.g., iron, iodine).

Iron

Mineral that acts as an oxygen carrier in hemoglobin and myoglobin.

Iodine

Mineral used to synthesize thyroid hormones.

Vitamins

Organic substances essential in small amounts; can be water-soluble or fat-soluble and may act as antioxidants.

Water-soluble vitamins

Vitamins that dissolve in water; include B vitamins and vitamin C.

Fat-soluble vitamins

Vitamins that dissolve in fats; include vitamins A, D, E, and K.

Simple sugars

Monosaccharides; quickly metabolized; can cause rapid spikes in blood glucose.

Complex carbohydrates

Polysaccharides (starches and fiber); metabolized slowly and provide steadier blood glucose.

Fiber

Indigestible carbohydrate that adds bulk, aids elimination, slows digestion, aids in weight control, and lowers cholesterol.

Saturated fats

Fats mainly from animal sources; higher intake linked to some diseases.

Unsaturated fats

Fats primarily from plants; generally associated with lower disease risk.

BMI (Body Mass Index)

A rough estimate of adiposity calculated from height and weight; categories include underweight, normal, overweight, obese.

Underweight

Low body weight; may result from starvation, eating disorders, rapid growth, illness; energy reserves are limited.

Overweight

Excess body weight from multiple factors; associated with higher risk of cardiovascular disease and diabetes.

Obesity

Severe overweight with increased health risks, including diabetes and heart disease.

Hypothalamus

Brain region that regulates body temperature and many metabolic processes.

Fever

Elevated body temperature triggered by pyrogens, typically due to infection or other causes.

Pyrogen

Substance that causes fever.

Radiation

Heat transfer from a warmer object to a cooler one without direct contact.

Evaporation

Heat loss when liquid water becomes vapor, cooling the body.

Heat exhaustion

Mild heat-related illness with elevated body temperature and symptoms like nausea, dizziness, and fatigue.

Heat stroke

Life-threatening condition with core temperature >40°C (104°F), confusion, seizures, or loss of consciousness; requires urgent treatment.