Metabolism and Homeostasis quiz Flashcards

Metabolism is the sum of the chemical processes of an organism that sustain its life.

ATP (Adenosine Triphosphate) is the main energy currency produced during cellular respiration, particularly through oxidative phosphorylation.

Basal metabolic rate is the minimum rate of energy consumption of an endotherm at rest.

Carbohydrates provide a quick initial boost of energy but don't last long, while proteins provide more sustained, long-term energy.

Endotherms generate their body heat internally through metabolism, while ectotherms absorb most of their body heat from external sources.

Smaller animals have a higher relative metabolic rate because they are more prone to heat loss and need to dedicate more energy to warming themselves.

Circadian rhythms are daily cycles that result in regular physiological and metabolic fluctuations.

Cortisol is a stress hormone that peaks early in the day to promote alertness and drops throughout the day.

Homeostasis is the regulation of physiological processes to maintain ideal conditions for survival.

Enzymes are proteins that catalyze chemical reactions in cells and function best in specific physiological conditions.

Conformers allow their internal conditions to fluctuate with the environment, while regulators actively maintain stable internal conditions.

Negative feedback is a regulation mechanism where the output of a system reduces the system's output to maintain balance.

The HPA axis is the hypothalamic-pituitary-adrenal axis, a stress hormone signaling system involving negative feedback.

Thermoregulation is a type of homeostasis that controls body temperature.

Homeotherms maintain a constant body temperature, while poikilotherms have body temperatures that vary with environmental conditions.

As an organism gets larger, its surface area to volume ratio decreases, which affects processes like molecular diffusion and heat loss.

Smaller organisms use relatively more energy compared to larger organisms due to their higher surface area to volume ratio.

Animals increase their surface area through flattening, folding, and branching structures, such as the folds in the brain and the villi in the intestines.

Basal metabolic rate (BMR) is the minimum rate of energy consumption of an endotherm at rest, measured when the organism is not physically exerting itself or stressed.

Warm-blooded organisms have higher metabolic rates than cold-blooded organisms because they need to consume energy to maintain their body temperature.

Homeostasis is the regulation of physiological processes to maintain stable internal conditions, which is crucial for the proper functioning of enzymes and overall survival.

Conformers allow their internal conditions to fluctuate with the environment, while regulators actively control their internal environment despite external changes.

Negative feedback is a regulatory mechanism where the output of a system reduces its own activity, helping to maintain balance, such as ATP inhibiting glycolysis.

The HPA axis involves the hypothalamus, pituitary gland, and adrenal cortex, coordinating the release of cortisol, which negatively feeds back to regulate stress hormone levels.

Positive feedback amplifies the output of a system, such as during childbirth, whereas negative feedback reduces the system's output to maintain stability.

Circadian rhythms are daily cycles of physiological and metabolic fluctuations, regulated by hormones like cortisol and melatonin.

The surface area of the intestine is increased by folds, villi, and microvilli, which enhance nutrient absorption during digestion.

The hypothalamus links the nervous and endocrine systems by coordinating the autonomic nervous system and the pituitary gland.

Smaller animals lose more heat to the environment relative to their size compared to larger animals, influencing their metabolic rate.