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Physiology

Field: Physiology

Sequence of Expressions

For the vast majority of animals, an organism's metabolic rate scales to the 34\frac{3}{4} power of the animal's mass.
Principle

Homeostasis

Living systems maintain a stable internal environment despite changes in external conditions.
The stroke volume of the heart increases in response to an increase in the volume of blood in the ventricles, before contraction, when all other factors remain constant.
Principle

Bohr Effect

Hemoglobin's oxygen binding affinity is inversely related both to acidity and to the concentration of carbon dioxide.
Deoxygenated blood increases its ability to carry carbon dioxide.
Principle

Reflex Arc

A neural pathway that controls a reflex, generally involving a receptor, sensory neuron, interneuron, motor neuron, and effector.
The strength of the heart's systolic contraction is directly proportional to its diastolic expansion with the result that under normal physiological conditions the heart pumps out of the right atrium all the blood returned to it without letting any back up in the veins.
Principle

Root Effect

An extreme Bohr effect present in some fish where an increase in acidity or carbon dioxide lowers the oxygen carrying capacity of hemoglobin, not just the affinity.