Homeostasis and Feedback Loops

Flashcards about Homeostasis and Feedback Loops

Physiology

The study of biological functions and how the body works.

Pathophysiology

Concerns how disease or injury affects physiological processes.

Comparative Physiology

Studies the differences and similarities in the functions of invertebrates and vertebrates.

Chemical Level

Atoms and molecules

Cellular Level

Cells

Tissue Level

Group of cells (4 types of tissues)

Organ Level

Composed of 2 or more tissue types

Organ System Level

Group of organs performing related functions

Organismal Level

The entire organism

Metabolism

Chemical reactions; food to energy; muscle contractions

Growth/Development

Materials from environment lead to increase in size/specialization

Responsiveness

Sense and respond to internal and external stimuli.

Adaptation

Alteration in anatomic structure, physiology, or behavior to increase reproductive success

Reproduction

New cells for maintenance, growth, repair, and reproduction.

Homeostasis

Maintenance of relatively constant internal environment of the body despite constant changes in the external environment

Regulated variables

Anything that can be measured in the body; examples include pH, blood glucose concentration, and body temperature.

Set point

Value around which normal range fluctuates; example: Body temp. is around 37°C, blood pH 7.34 – 7.45

Deviation

Change from the set point

Correction (compensation)

How much the body adjusts depends on how great the deviation is from the set point.

Sensor (receptor)

Monitors physiological value and reports it to the control center

Control Center (integrating center)

Compares value to normal range and communicates with the effector

Effector

Causes a change to reverse the situation and return the value to normal range

Antagonistic Effectors

Have opposing effects. As the activity of one increases, the activity of the other decreases

Intrinsic control

Built into the organ being regulated.

Extrinsic control

Control by the nervous system and endocrine system

Positive Feedback

Intensifies the change rather than reversing it back to homeostasis