Chapter 30 Notes

Body Organization

Body has 4 levels of Structural Organization

• Cell

• Tissue

• Organ

• Organ System

4 Kinds of Tissues

• 1. Epithelial– Lines body surfaces and protects from dehydration

and damage

• 2. Nervous– Composed of nerve cells to carry information

• 3. Connective– Support, protect and insulate body

4. Muscle• Enable movement of body structures

– 1. Skeletal-moves bones in trunk and limbs (voluntary)

–2. Smooth-lines blood vessels, esophagus, etc., (involuntary)

3. Cardiac-found only in heart

• Tissues are grouped into organs, which are then grouped into organ systems.

• Organs are housed in large fluid-filled cavities called Body Cavities that protect them.– Cranial Cavity– Spinal Cavity– Thoracic Cavity– Abdominal Cavity

Homeostasis

• The relatively constant internal physical and chemical conditions that organisms maintain despite changes in internal and external environments.

Feedback Inhibition

• Monitoring and keeping internal conditions within a certain range.

• For example, the maintenance of body temperature.