1. RESPIRATORY AND CIRCULATORY SYSTEMS

2. CIRCULATORY SYSTEM pgs 933-939 Moves fluid throughout the body

3. STRUCTURES Heart – muscular organ that pumps blood to all parts of the body.

4. Vessels: smooth muscle surrounded by connective tissue a. arteries – carries blood from the heart b. veins –carries blood to the heart c. capillaries –narrow blood vessels that pass blood (cells) in single file.

6. MOVEMENT OF BLOOD right side: (deoxygenated) blood from body to heart to lungs left side: (oxygenated) blood from lungs to the heart to body.

7. RESPIRATORY pgs 946-950

8. EXTERNAL FUNCTION exchange of gases between atmosphere and blood

9. MECHANISM Large skeletal muscle (diaphragm) contracts pulling lungs down causing them to fill with air

10. INTERNAL FUNCTION exchange of gases between blood and cells Gases diffuse across due to concentration gradients lungs (alveoli)  capillaries (carrying blood)

11. Figure 42.UN02 Exhaled air Alveolar epithelial cells Pulmonary arteries Systemic veins Heart CO 2 O2O2 Body tissue Systemic capillaries Systemic arteries Pulmonary veins Alveolar capillaries Alveolar spaces Inhaled air CO 2 O2O2

12. Homeostasis: Blood pH of about 7.4 CO 2 level decreases. Stimulus: Rising level of CO 2 in tissues lowers blood pH. Response: Rib muscles and diaphragm increase rate and depth of ventilation. Carotid arteries Aorta Sensor/control center: Cerebrospinal fluid Medulla oblongata Figure 42.29

13. HOMEOSTASIS Breathing control centers are in the brain The rate and depth of breathing in response to pH changes (O 2 and CO 2 concentrations)