1. Chapter 6
Body Systems

2. Anatomy – structure
Physiology – function
Homeostasis – stable internal environment

3. Circulatory System
Pumps blood throughout body, delivering oxygen and nutrients to cells; carbon dioxide and wastes away from body
Made of: heart, blood, arteries, & veins

4. Two pathways Systemic circulation
- heart pumps oxygenated blood away thru arteries to cells
- cells absorb O2 ; release CO2 & other wastes
- some waste – eliminated by kidneys, etc
- carries blood back to heart

5. Pulmonary circulation
- heart pumps deoxygenated blood, CO2 & wastes to lungs
- blood releases CO2, wastes; picks up O2
- oxygenated blood flows back to heart to enter systemic circulation

6. Blood Fn: distribute heat, transport O2 and wastes
Made of: red blood cells, white blood cells, platelets, & plasma

7. RBCs = erythrocytes
Large surface area – efficient gas exchange
Hemoglobin binds to oxygen & transports it
Form in bone marrow; live ~120 days
Formation depends upon oxygen levels

8. WBCs = leukocytes
Protect body against infection; fight viruses & bacteria
Healthy – 5,000 – 10,000 WBCs per mL blood
Infection – 10,500+ (ex. appendicitis)
Immune system suppressed – below 3,500 (ex. HIV, flu)

9. Platelets = thrombocytes
= cell fragments surrounded by cell membrane
Form blood clots (release clotting factors)

10. Plasma – liquid portion of blood
92 % water, rest = salts, nutrients, enzymes, proteins, dissolved gases, etc
Transports nutrients, vitamins, and gases
Regulates pH, maintains fluid balance, controls body temp

11. Path of blood thru Heart
Heart – 2 atria (top), 2 ventricles (bottom)
Capillaries – smallest vessels
Alveoli – tiny air sacs in lungs
Arteries - away from heart
Veins – to heart

12. Deox blood to right atrium
To right ventricle thru tricuspid valve
Pumped into pulmonary artery to lungs
Gas exchange - CO2 from caps into alveoli; O2 from alveoli into caps
Ox. blood to left atrium thru pulmonary vein
To left ventricle thru bicuspid valve
To aorta to body

13. Path