Control of Energy, Metabolic Rate, and Body Temperature

These flashcards cover key concepts related to energy control, metabolic rates, hormonal regulation, and body temperature regulation.

Metabolic Rate

Total energy used over time, including basal metabolism, activity, and thermoregulation.

Basal Metabolic Rate (BMR)

Energy used at rest, measured under fasting conditions, resting state, and neutral temperature.

Absorptive State

The metabolic state that occurs during/after eating, where nutrients enter the bloodstream and energy is stored.

Postabsorptive State

The metabolic state between meals where the body uses stored energy and maintains blood glucose.

Glycogenolysis

The breakdown of glycogen into glucose, occurring in the liver as a rapid response to low blood glucose.

Gluconeogenesis

Formation of glucose from non-carbohydrates, such as amino acids and glycerol, occurring in the liver.

Insulin

Hormone released when blood glucose is high, increasing glucose uptake, stimulating glycogen formation, and promoting fat storage.

Glucagon

Hormone released when blood glucose is low, stimulating glycogen breakdown and promoting gluconeogenesis.

Blood Glucose Regulation

Controlled by insulin (lowers glucose) and glucagon (raises glucose) through a feedback system.

Energy Balance

The relationship between energy intake and expenditure; stable weight occurs when intake equals expenditure.

Body Mass Index (BMI)

A measure to estimate body fat calculated as weight in kilograms divided by height in meters squared.

Ectotherms

Animals that rely on external heat sources to regulate body temperature.

Endotherms

Animals that generate internal heat to maintain body temperature.

Homeostasis

The process of maintaining a stable internal environment, including regulation of blood glucose and body temperature.

Hormonal Regulation of Appetite

Controlled by the hypothalamus through signals such as blood glucose levels and hormones like leptin and ghrelin.

Thermoregulation

The physiological processes that maintain body temperature within a narrow optimal range.

Heat Exchange Mechanisms

Methods of transferring heat, including radiation, conduction, convection, and evaporation.

Glucose Sparing

A metabolic adaptation where cells switch to fatty acids for energy during fasting to preserve glucose for the brain.

Obesity

A condition defined by an excess of body fat, related to energy intake exceeding expenditure.

BMI Classification

Categories of body mass index: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), obese (≥30).

Exercise Impact on Metabolic Rate

Exercise increases ATP demand, oxygen consumption, and requires rapid fuel mobilization.