homeostasis - body's maintenance of a stable environment
receptors - molecule or cell that provides information about the environment
control center
... [Show More] (and set point) - indicates correct value (e.g. body temp)
effectors - What elicits a response that alters conditions within the body's internal environment. (e.g.
muscles and glands)
negative feedback - When receptors measure deviations from the set point, effectors are activated and
conditions are returned toward the set point and effectors gradually shut off. This movement toward
homeostasis and balance is called .........
positive feedback - Homeostatic mechanisms that function when changes byeffectors move the body
away from normal conditions, causing more changes, is called...... (examples are blood clotting and labor
contractions)
organelles, cells, tissues, organs, organ systems, organism - Levels of organization
organelle - Cell components that perform a specific function
cells - Basic unit of structure and function
tissues - Groups of cells organized into layers or masses that have specific functions
organs - Structures that perform a specialized function (comprised of tissues)
Organ systems - Groups of organs that function together closely
Organism - Comprised of an interacting organ system
superior - above, or closer to the head
inferior - below, or closer to the feet
Anterior (Ventral) - Toward the front
Posterior (Dorsal) - Toward the back
medial - Toward the midline
lateral - Away from the midline (closer to the sides)
Median (saggital) plane - Imaginary vertical line dividing the body into right and left portions
Coronal/Frontal plane - Imaginary vertical line dividing the body into anterior and posterior portions
Transverse (cross-sectional) - Imaginary horizontal line dividing the body into superior and inferior
Dorsal cavities (near the back) - Cranial and spinal cavity
Cranial cavity - Cavity that contains the brain
Spinal cavity (vertebral) - Cavity that contains the spinal cord and vertebrae
orbits, nasal, oral, thoracic, mediastinum, pericardial, pleural, and abdominopelvic (peritoneal) - Ventral
cavities (near the front of the body) [Show Less]