Circulatory System

1
Circulatory System
2
The Heart

• A muscular organ that pumps blood throughout your
  body.
• Four chambers
• Atria (left/right) move the blood from the body
  into the heart. They pump the blood into the
  ventricles
• Ventricles(left/right) pump the blood out of the
  heart
• Left ventricle pumps the blood out to the body.
• Right ventricle pumps the blood to the lungs

3
The Heart

• Between the chambers are valves.
• Valves allow the blood to flow in only one
  direction
• lub dub is the opening and closing of the valves

4
Circulatory System

• The circulatory system is made up of blood
  vessels
• All your blood vessels lined up would be about
  100 000 km

5
Types of Blood Vessels

• Arteries are blood vessels that carry blood away
  from your heart.
• Most carry oxygenated blood.
• Arteries are thick walled and elastic to handle
  the pressurized flow.
• The largest artery is the aorta.
• Arteries branch into arterioles, and finally
  capillaries.
• Capillaries are where gases and nutrients are
  exchanged with the cells

6

• After leaving the capillaries, the blood is
  deoxygenated
• Blood is carried back to the heart through tiny
  venules and into the veins.
• Veins have valves that prevent the backflow of
  blood.
• Blood returns to the heart through the major
  veins the superior vena cava, and the inferior
  vena cava.

7
(No Transcript)
8
Components of Blood

• Blood transports oxygen, nutrients, and water to
  your cells and carries carbon dioxide and wastes
  away from your cells.
• Blood also carries cells that fight infection and
  heal wounds.
• 55 of the 5L of blood is plasma.
• Plasma water, proteins and minerals, dissolved
  salts.
• 45 of the 5L of blood are the Red blood cells,
  white blood cells, and platelets.

9

• Red blood cells carry oxygen and carbon dioxide.
  
• Formed in bone marrow, liver, and spleen.
• Hemoglobin carries the oxygen.
• White blood cells fight infection.
• Much larger than RBCs
• Platelets help clot the blood by forming a scab.

10
Respiratory System

• When you breathe, you inhale oxygen and exhale
  carbon dioxide.
• Your lungs deliver the oxygen, and excrete carbon
  dioxide.
• Breathing brings the oxygen in, the air is
  filtered by cilia and mucus.
• Air travels down the pharynx and larynx (voice
  box), and then the trachea.
• At the base of the trachea are the bronchi, which
  branch into smaller tubes called bronchioles.
• Finally, the air reaches tiny sacs called alveoli.

11
Gas Exchange

• Alveoli are tiny, thin-walled sacs.
• Each alveolus is surrounded by capillaries.
• O2 diffuses out of the alveolus into the blood
  and binds with red blood cells, and CO2 diffuses
  into the alveolus.