1. Body Organization and Homeostasis Section 1

2. Cells The levels of organization in the human body consist of cells, tissues, organs, and organ systems Cell is the basic unit of structure and function in a living thing Structures of cells Functions of cells – Cell membrane – Nucleus – Cytoplasm

3. Tissues Tissue Muscle tissue Nervous tissue Connective tissue Epithelial tissue

4. Organs and Organ Systems Organ Organ systems

5. Homeostasis Homeostasis is the process by which an organisms internal environment is kept stable in spite of changes in the external environment Homeostasis in Action Maintaining Homeostasis Stress and Homeostasis