1. Homeostasis

2. What is Homeostasis? Maintenance of a stable internal environment.
Regulated through control systems which have
receptors -monitor change (nerves)
control center - contains the “ideal value” (brain)
Effectors - provide response (muscles, glands)

3. Negative Feedback
Causes change in a direction opposite the initial change. Returns to the “ideal” value.
Example:
Normal body temp is 98.6 degrees F
When hot, sweat to decrease temp
When cold, shiver to increase temp

4. Positive Feedback
Response to change is an increased departure from the normal condition.
Example:
Illness causes a fever. The increase in body temp stimulate the release of chemicals that will cause the body temp to continue to increase.

5. Homeostasis Video
What is it, why important: Positive and Negative Feedback Loops

6. Nervous System

7. Function
Gather and respond to information about the internal and external environment.

8. Structures of the Nervous System
Brain
Spinal cord
Peripheral nerves (come off brain and spinal cord)

9. Lobes of the Brain Frontal Problem-solving, judgment, planning
Temporal
Speech and hearing
Occipital
Vision
Parietal
Sensory information

10. Other Brain Structures
Cerebellum
Controls muscle movement/balance
Brainstem
Controls basic life functions (heart rate, breathing, digestion)

11. Cardiovascular
System

12. Structure and Function
Structures: heart, blood vessels, blood
Function:
transport oxygen, nutrients, and waste.

13. Structures of the Heart
Atria
Receive blood
Ventricles
Pumps blood to body
Aorta
Largest artery in the body
Superior/Inferior Vena Cava
Bring blood to the heart from the body
Pulmonary arteries and veins
Transport blood to/from lungs

14. Blood Vessels Arteries: take blood from the heart
Veins: take blood to the heart
Capillaries: smallest blood vessels, where gas exchange occurs

15. Did you know…
The human heart creates enough pressure to squirt blood 30 feet!
Licorice can raise your blood pressure (blood pressure refers to the pressure in the arteries)

16. Respiratory System

17. Structures
Nose, sinuses, larynx, trachea, bronchi, and alveoli.

18. Functions of the Respiratory System
Obtain oxygen (needed for cell respiration)
Remove carbon dioxide

19. Cool Respiratory System Facts
An average adult has about 300 million alveoli!
If all the capillaries on the alveoli were laid end to end they would be 620 miles long!