Organ Systems and Homeostasis

PH 508-517

Previously in life science…

• You learned that cells are the basic building blocks of living things. Now, you will learn how those cells are organized in levels to create a whole organism.

• Do you remember the function of the nucleus?

A. the nucleus directs the cell’s activities!

B. Do you remember the function of the cell membrane?

B. the membrane forms outside boundary of the cell!

1. Identify the levels of organization in the body.

1. Cells

2. Tissues

3. Organs

4. Organ Systems

5. Whole Organism

Complex

Simple

2. What is a cell?

• The basic unit of structure and function in living things

3. What is a tissue?

• The “thing” you use to blow your nose!!!

• A group of cells that perform the same function

4. What are the 4 basic tissue types?

1. Muscle tissue – can shorten to make you move

ex: muscle & heart

2. Nerve tissue – carry messages throughout body

ex: brain & spinal cord

3. Connective tissue – supports and connects the body

ex: blood, fat, bones

4. Epithelial tissue – covers surfaces of body

ex: skin & internal organs

• What is the job of muscle tissue?

To make parts of the body move

5. What are organs?

• A group of tissues that perform a function.

ex: stomach, heart, brain, lungs

6. What are organ systems?

• A group of organs that work together to perform a major function

7. What are the major organ systems of the body?

Movement:

• Integumentary

• Skeletal

• Muscular

Life Processes:• Circulatory• Respiratory• Digestive• Excretory• Immune• Reproductive

Control:• Nervous• Endocrine

8. Why do organ systems work/function?

• Because of the contributions of the individual organs, tissues, and cells!

9. What happens if part of an organ system fails?

• Failure of any part can affect the entire system, potentially causing organ system failure

• Example: heart attack

10. What is homeostasis?

• The process by which an organism's internal environment is kept stable despite changes in the external environment.

• Ex: body temperature!

What did you learn today?

• You learned how cells are organized in levels to create a whole organism: cells, tissue, organ, organ system.

Tissue Observations

1. Fold paper into fourths

2. Create 2 circles

3. Label top half “blood”

4. Label bottom half “nerve”

Tissue Observations

blood

nerve

_____________________

_____________________

Blood

Nerve Tissue