Energy Metabolism Flashcards

Flashcards on Energy Metabolism

Energy Metabolism

All chemical reactions by which the body obtains and spends energy.

Anabolic process

Building of substances.

Catabolic process

Breakdown of substances.

Oxidation

Losing electrons.

Reduction

Gaining electrons.

Oxidation in cellular metabolism

Results in ATP formation (energy currency).

Metabolic coupling

One metabolic reaction cannot proceed without the reactions it is linked to.

1st law of thermodynamics

Energy cannot be created nor destroyed; in a closed system, energy is constant, but can be transformed.

Steady state

Energy intake = Energy Expenditure (and Energy storage).

Positive energy balance

More energy coming into the body than needed, stored as adipose tissue.

Negative energy balance

Extra energy comes from storage.

1g of carbohydrate

4 kcal or 17 kj.

1g fat

9 kcal = 38kj.

1g protein

4 kcal = 17 kj.

1g alcohol

7 kcal = 30kg.

Calorimetry

The science of measuring heat production.

Indirect calorimetry

Measure of O2 consumption and CO2 production as an indicator of heat production.

Respiratory Quotient (RQ)

Ratio of moles CO2 produced per moles O2 consumed at the tissue level.

2nd law of thermodynamics

Chemical transformations always result in a loss of free energy available to drive metabolic process.

Gibbs Free energy (G)

Free energy available to drive metabolic processes.

Metabolic rate

Measure energy balance.

Resting metabolic rate

Estimate of energy required while at rest.

Basal Metabolic rate

Clinical measurement of metabolism, measured under several standardized conditions.

ATP

Adenosine Triphosphate.

Glycolysis

Breaking glucose down to pyruvic acid.

Glycogenesis

Taking glucose and forming glycogen.

Glycogenolysis

Break down of glycogen to glucose.

Gluconeogenesis

Creation of new glucose.

Beta Oxidation

loss of electrons.

Lipolysis

Taking triglyceride and breaking it down to fatty acids and glycerol.

Lipogenesis

Building up.

Liver

Important supplier.

Muscle

Tends to be a consumer.

Red blood cells

Only use anaerobic glycolysis.