Metabolism: Nutrients and Their Functions

These flashcards cover key concepts related to metabolism, including macronutrients, micronutrients, and their functions, as well as metabolic pathways and processes involved in energy production.

Nutrients

Any substance that the body uses for growth, repair, and maintenance.

Macronutrients

Nutrients that make up most of our diet; larger in size, including carbohydrates, lipids, and proteins.

Micronutrients

Vitamins and minerals required in minimum amounts.

Carbohydrates

Substances mostly derived from plants, dairy, and small amounts in meat that provide energy, constituting 45-60% of daily caloric intake.

Glycocalyx

A sugar coating around cells that helps the immune system recognize self vs non-self.

Complex carbohydrates

Nutrient-dense carbohydrates from grains and plant-based sources that are unprocessed.

Empty carbohydrates

Processed sugars that are high in calories but provide no nutrients, such as soda and candy.

Triglycerides

A type of lipid that includes saturated and unsaturated fats, important for energy storage.

Cholesterol

A lipid that is 85% made by the liver, important to limit due to its potential to cause plaque build-up.

Complete proteins

Proteins that contain all essential amino acids, found in meat, eggs, fish, and dairy.

Incomplete proteins

Proteins missing some essential amino acids, commonly found in nuts, seeds, and legumes.

Positive nitrogen balance

When protein synthesis equals protein breakdown, often seen in growth or tissue repair.

Negative nitrogen balance

When protein breakdown exceeds protein synthesis, often due to stress or malnutrition.

Vitamins

Essential micronutrients that function as coenzymes to assist enzymes in chemical reactions.

Metabolism

All chemical reactions in the body, including anabolic (building) and catabolic (breaking down) reactions.

Oxidation

The loss of electrons/hydrogen during a chemical reaction.

Reduction

The gain of electrons/hydrogen during a chemical reaction.

Glycolysis

The first stage of carbohydrate metabolism, converting glucose into pyruvic acid and yielding ATP.

Krebs cycle

An aerobic metabolic pathway where acetyl CoA is processed to produce ATP and reduced coenzymes.

Electron transport chain and oxidative phosphorylation (ETC and OP)

The final stage of carbohydrate metabolism generating the bulk of ATP using reduced coenzymes.

Glycogenesis

The process of converting glucose to glycogen for storage when glucose levels are high.

Glycogenolysis

The process of converting glycogen back to glucose-6-phosphate when glucose levels are low.

Lipogenesis

The synthesis of triglycerides occurring when ATP demand is low.

Lipolysis

The breakdown of triglycerides occurring when ATP demand is high.

Transamination

The process of transferring an amine group from an amino acid to a keto acid, enabling amino acids to enter the citric cycle.