1. Respiratory System Cardiovascular System

2. The Respiratory System

3. Main Parts of the Respiratory System NOSE – primary passageway into and out of the respiratory system (warms, moistens & filters air) PHARYNX – throat; branches into two tubes-the larynx for air and the esophagus for food (digestive system) LARYNX – voicebox; contains the vocal cords

4. Main Parts of the Respiratory System TRACHEA – windpipe; large tube that leads from the larynx to the lungs BRONCHI – 2 tubes-one bronchus goes to each lung; branches into bronchioles LUNGS – large spongelike organs that take oxygen from the air and deliver it to the blood

5. Inside the Lungs Each bronchus branches into thousands of tiny tubes called bronchioles Each bronchiole branches to form thousands of tiny sacs called alveoli The alveoli is where oxygen and carbon dioxide are exchanged

6. Breathing Lungs DO NOT contain the muscles for breathing Diaphragm contracts and moves down-increases the chest cavity’s volume Rib muscles contract and lift your rib cage, causing it to expand Air is sucked in

7. The Cardiovascular System

8. The Heart Muscular organ about the size of your first Left side and right side separated by a thick wall Heart has 4 chambers Atrium—upper chamber— one per side Ventricle—lower chamber— one per side Valves—flaplike structures (lub-dub)

9. Path of Blood Through the Heart 1. right atrium receives oxygen-poor blood from the body 2. right atrium contracts and squeezes blood into the right ventricle 3. right ventricle contracts and pushes blood out to the lungs

10. Path of Blood Through the Heart 4. left atrium receives oxygen-rich blood from the lungs 5. left atrium contracts and squeezes blood into the left ventricle 6. left ventricle contracts and pushes blood out to the body

11. Blood Vessels Arteries—direct blood away from the heart Capillaries—smallest blood vessels in the body Veins—direct blood back to the heart Blood Pressure—force exerted by blood on the inside walls of a blood vessel

12. Flow of Blood Through the Body Pulmonary circulation— circulation of blood between your heart and lungs Systemic circulation— circulation of blood between the heart and the rest of the body