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.