1. Warm up
Reflect upon the Cell Processes Test you took on Thursday. Answer the following questions honestly. Write answers on a piece of notebook paper.
What grade do you think you made?
How much time did you spend studying? What did you do to study?
What did you actually make on the test?
Why did you make this grade?

2. Cellular Organization
Five Levels of Organization
Within the Human Body

3. Levels of Organization
From smallest to largest:
Cells
Tissues
Organs
Organ systems
Organism

4. Cells
Cell – basic unit of structure and function in a living thing

5. Tissues
Tissue – group of similar cells that perform the same function.
The human body consists of four basic types of tissue:
Muscle tissue
Nerve tissue
Connective tissue
Epithelial tissue

6. Muscle Tissue
Muscle tissue – makes parts of your body move by contacting (or shortening)

7. Nerve Tissue
Nerve tissue – carries messages back and forth between the brain and every other part of the body.

8. Connective Tissue
Connective Tissue – provides support for your body and connects all its parts.
Ex:
Bone – supports & protects
Fat – insulation & energy storage
Blood

9. Epithelial Tissue
Epithelial tissue – covers the surfaces of your body (inside & out).

10. Organs Organ – structure composed of different kinds of tissue.
Each organ performs a specific job.
Ex:
Heart – pumps blood throughout the body
Stomach – breaks down food so that it can be absorbed by the intestines.

11. Organ Systems
Organ system – a group of organs that work together to perform a major function.
Ex:
Circulatory system – heart, blood vessels, blood
See “Systems of the Human Body” chart for information on each body system.

13. Homeostasis
The different organ systems work together and depend on one another.
Ex:
Respiratory, digestive & circulatory systems work together to fuel muscles with the energy they need.
The systems of the human body work together to maintain homeostasis.

14. Summary
What are the levels of organization within the human body (from smallest to largest)?
Name two body systems that work together to maintain homeostasis in the human body.