ch25

These flashcards cover key vocabulary terms related to metabolism, nutrition, and energetics, aiding in understanding the concepts discussed in the lecture.

Metabolism

The sum of all chemical and physical changes that occur in body tissues.

Metabolic activity

The chemical reactions of the body involving the breakdown of organic molecules to obtain energy.

ATP

Adenosine triphosphate, the energy currency of the cell.

Catabolism

The breakdown of large molecules into smaller ones, releasing energy.

Anabolism

The process of converting small molecules into larger ones, requiring energy.

Nutrient pool

All available nutrient molecules distributed in blood.

Triglycerides

The most abundant storage lipids, consisting primarily of fatty acids.

Glycogen

The most abundant storage carbohydrate, a branched chain of glucose molecules.

Coenzymes

Molecules that act as intermediaries in chemical reactions, accepting and transferring electrons.

Oxidation

The loss of electrons or hydrogen by a molecule.

Reduction

The gain of electrons or hydrogen by a molecule.

Electron transport chain

A series of protein complexes in mitochondria that transfer electrons to produce ATP.

Chemiosmosis

The process of ATP generation powered by the movement of protons across a membrane.

Glycolysis

The breakdown of glucose into pyruvate, yielding ATP and NADH.

Citric Acid Cycle (Krebs Cycle)

A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA.

Oxidative phosphorylation

The process that produces ATP from the transfer of electrons and the establishment of a proton gradient.

Acetyl-CoA

A central molecule in metabolism that enters the citric acid cycle.

Beta-oxidation

The metabolic process of breaking down fatty acids to generate acetyl-CoA.

Glycogenesis

The formation of glycogen from excess glucose.

Glycogenolysis

The breakdown of glycogen to release glucose monomers.

Nitrogen balance

The difference between total nitrogen consumed and the amount excreted.

Positive nitrogen balance

Condition in which nitrogen intake exceeds nitrogen output, as seen in growth or recovery.

Negative nitrogen balance

Condition in which nitrogen output exceeds nitrogen intake, indicating potential muscle wasting.

Malnutrition

An unhealthy state resulting from nutrient imbalance.

Complete proteins

Proteins that contain all essential amino acids in sufficient quantities.

Incomplete proteins

Proteins that lack one or more essential amino acids.

Hypovitaminosis

Vitamin deficiency due to inadequate vitamin intake.

Hypervitaminosis

A condition resulting from excessive intake of vitamins, leading to toxic effects.

Fat-soluble vitamins

Vitamins that are absorbed along with lipids and stored in body fat.

Water-soluble vitamins

Vitamins that dissolve in water and are readily excreted from the body.

Fever

A body temperature greater than 37.2ºC (99ºF), which can occur for various reasons.

Thermoregulation

The biological process that maintains body temperature within a certain range.

Basal metabolic rate (BMR)

The rate of energy expenditure while at rest to maintain vital functions.

Obesity

A condition where body weight exceeds 20 percent above the ideal weight.

Thermogenesis

The process of heat production in organisms, primarily through metabolism.

Ketone bodies

Organic compounds produced by fatty acid metabolism that can serve as energy sources.

Ketonemia

The presence of ketone bodies in the bloodstream, which can alter blood pH.

Lipid catabolism

The breakdown of lipids into fatty acids and glycerol for energy production.

Beta oxidation

A metabolic process that breaks down fatty acids into acetyl-CoA.

Adipose tissue

Tissue that stores fat in the form of triglycerides.

Amino acid catabolism

The process of breakdown of amino acids for energy or conversion to other compounds.

Urea cycle

A series of chemical reactions that convert toxic ammonia to urea for excretion.

Transamination

The process of transferring an amino group to a keto acid to form a new amino acid.

Deamination

The removal of an amino group and hydrogen atom from an amino acid to produce a toxic ammonium ion.

Nervous tissue

Tissue that does not store nutrients and relies on a constant supply of glucose.

Absorptive state

The metabolic state following a meal when nutrients are being absorbed.

Postabsorptive state

The fasting state where the body relies on internal energy reserves to maintain glucose levels.

Free fatty acids (FFAs)

Fatty acids not bound to glycerol, can freely diffuse across plasma membranes.

Chylomicrons

Lipid-protein complexes that transport absorbed lipids into the bloodstream.

Lipoproteins

Complexes of lipids and proteins that transport lipids through the bloodstream.

Hypertension

High blood pressure, often associated with obesity.

Ketoacidosis

A serious complication caused by high levels of ketone bodies leading to blood acidification.

Lipogenesis

The synthesis of lipids from non-lipid precursors.

Digestive tract

The organ system responsible for the digestion and absorption of nutrients.

Epithelia

Tissue that lines the surfaces of organs and structures of the body.

Intrinsic factor

A protein essential for the absorption of vitamin B12 in the intestines.

Calorimetry

The measurement of energy expenditure in the body.

Kilocalorie (kcal)

Energy required to raise the temperature of 1 kilogram of water by 1 degree Celsius.

Epinephrine

A hormone that increases metabolic rate and energy availability.

Thyroxine

A hormone produced by the thyroid gland that regulates metabolism.

Acclimatization

The physiological adjustment of an organism to changes in its environment.

Brown fat

A type of adipose tissue that generates heat through fat metabolism.