1. KEY CONCEPT The respiratory and circulatory systems bring oxygen and nutrients to the cells.

2. There are three major functions of the circulatory system.
The respiratory and circulatory systems work together to maintain homeostasis.
There are three major functions of the circulatory system.
transporting blood, gases, nutrients
collecting waste materials
maintaining body temperature
Oxygen-poor blood
Oxygen-rich blood

3. The circulatory system moves blood to all parts of the body.
The system includes the heart, arteries, veins, and capillaries.
heart pumps blood throughout body
arteries move blood away from heart
veins move blood back to heart
capillaries get blood to and from cells
veins
arteries

4. The tissues and structures of the heart make it an efficient pump.
Cardiac muscle tissue works continuously without tiring.
NORMAL HUMAN HEART

5. The heart has four chambers: two atria, two ventricles.
Valves in each chamber prevent backflow of blood.
aortic valve
left atrium
mitral valve
left ventricle
septum
pulmonary valve
right atrium
tricuspid
right ventricle
Muscles squeeze the chambers in a powerful pumping action.

6. Blood flows through the heart in a specific pathway.3 1 4 2

7. KEY CONCEPT The respiratory system exchanges oxygen and carbon dioxide.

8. The respiratory system is where gas exchange occurs.
picks up oxygen from inhaled air
expels carbon dioxide and water
nose
sinus
mouth
epiglottis
trachea
lungs

9. The respiratory system moves gases into and out of the blood.
The lungs contain the bronchi, bronchioles, and alveoli.
Millions of alveoli give the lungs a huge surface area.
The alveoli absorb oxygen from the air you inhale.
alveoli
bronchiole

10. Breathing involves the diaphragm and muscles of the rib cage.
Air flows from areas of high pressure to low pressure.
Air inhaled.
Muscles contract and
rib cage expands.
Diaphragm flattens
and moves downward.
Air exhaled.
Muscles and
rib cage relax.
Diaphragm relaxes
and rises.

11. Gas exchange occurs in the alveoli of the lungs.
Oxygen and carbon dioxide are carried by the blood to and from the alveoli.
oxygen diffuses from alveoli into capillary
oxygen binds to hemoglobin in red blood cells
carbon dioxide difuses from capillary into alveoli
ALVEOLI
GAS EXCHANGES
alveolus
capillary
co2 o2
Co2 diffuses
into alveolus.
O2 diffuses
into blood.
capillaries

12. Smoking is the leading cause of lung diseases.