Module 1 Homeostasis Feedback and Terminology

Homeostasis

The capacity to maintain relatively stable internal conditions despite changes in the external environment.

Negative feedback

A control mechanism that reduces the size of the stimulus.

Organ systems

Groups of organs that work together to perform complex functions necessary for the survival of the organism.

Anatomical position

A standard reference point in which the body is standing upright, facing forward with palms facing forward.

Flexion

The bending of a joint.

Extension

The straightening of a joint.

Abduction

Movement away from the midline of the body.

Adduction

Movement toward the midline of the body.

Cavities of the body

The major hollow spaces within the body that contain organs, such as the dorsal and ventral cavities.

Metabolism

Chemical reactions in the body that generate energy and are essential for growth and bodily processes.

Stimulus

A change in variable that can trigger a response if it moves outside of its normal range.

Effector

The component that takes action to change or modify the stimulus size in a control mechanism.

Respiratory system

The organ system that exchanges oxygen and carbon dioxide between the body and the environment.

Urinary system

The organ system responsible for the removal of waste from the body, primarily through urine.

Reproductive system

The organ system that produces gametes and is vital for the survival of the species.

Dorsal cavity

The body cavity that contains the cranial and vertebral cavities, housing the brain and spinal cord.

Ventral cavity

The body cavity that includes the thoracic and abdominopelvic cavities.

Protraction

The movement of a body part forward, such as moving the mandible anteriorly.

Retraction

The movement of a body part backward, such as moving the mandible posteriorly.

Superior/inferior

Terms used in anatomy to describe the position of structures relative to each other; superior means above and inferior means below.

Medial/lateral

Terms that describe the position of structures; medial is toward the midline, lateral is away from the midline.