1. 7.4 Homeostasis & Cells p214
Q: How do individual cells maintain homeostasis?
A: Unicellular organisms grow, respond to the environment, transform energy & reproduce.

2. The Cell as an Organism
Homeostasis-maintain constant internal conditions.
Cells must:
Grow
Respond to environment
Transform energy
Reproduce

3. Multicellular Life
Q: How do the cells of multicellular organisms work together to maintain homeostasis?
A:They become specialized for particular tasks & communicate with one another.
Cell Specialization-different cells, play different rolls, specific tasks.
Specialized for both animals & plants.

4. Levels of Organization
Smallest to largest
Cell
Tissue
Organ
Organ system

5. Cells communicate using receptors-specific protein to whose shape fits that of a specific molecular messenger, such as a hormone.