Science- Circulatory System

Pulmonary System

Carries deoxygenated blood from the heart to the lungs

Systemic Circulation

Carries oxygenated blood to the rest of the body through the arteries

Vein

Carries blood back into the heart,

Thin outer wall, thin inner layer, wider central tube (lumen )

Artery

carries blood away from the heart,

thick outer wall, thick inner layer of muscle and fiber

capillary

carries blood to and from the body cells

only one cell thick

Heart

pumps the blood throughout the body

10 Right Atrium

• Receives deoxygenated blood from the body through the superior and inferior vena cavae.

12 Right Ventricle

• Pumps deoxygenated blood to the lungs via the pulmonary arteries.

2 Left Atrium 

• Receives oxygenated blood from the lungs through the pulmonary veins.

4 Left Ventricle 

• Pumps oxygenated blood to the rest of the body through the aorta.

11 Tricuspid Valve

• Located between the right atrium and right ventricle; prevents backflow of blood from the right ventricle into the right atrium.

13 Pulmonary Valve

• Located between the right ventricle and the pulmonary artery; prevents backflow of blood from the pulmonary artery into the right ventricle.

 3 Mitral Valve (Bicuspid Valve) 

• Located between the left atrium and left ventricle; prevents backflow of blood from the left ventricle into the left atrium.

5 Aortic Valve

• Located between the left ventricle and the aorta; prevents backflow of blood from the aorta into the left ventricle.

6 Aorta (7 Body Cells) (8 Veins)

• The largest artery in the body, which carries oxygenated blood from the left ventricle to the rest of the body.

14 Pulmonary Arteries (15 Lungs) (Repeat)

• Carry deoxygenated blood from the right ventricle to the lungs.

 1 Pulmonary Veins

• Carry oxygenated blood from the lungs to the left atrium.

9 Superior Vena Cava 

• Returns deoxygenated blood from the upper body to the right atrium.

9 Inferior Vena Cava 

• Returns deoxygenated blood from the lower body to the right atrium.

Oxygenated Blood

• Bright Red. Carries Oxygen

Deoxygenated Blood

• Darker Red. Carries Carbon Dioxide

Red blood cells (RBC)

• Blood is made up of a number of different elements. The most common cell in blood is the red blood cell.

• Also called erythrocytes. (erythro-red;cytes-cells)

• Disc-shaped.

• Made in the bone marrow. (2 or 3 million cells per sec)

• Contain a red-coloured compound called hemoglobin which bonds with oxygen to form oxyhemoglobin.

• Transport oxygen to the tissues.

• 5 000 000 in each mm3

• They live for about 120 days shuttling oxygen and carbon dioxide (worn out goes to spleen and the liver)

White blood cells (WBC)

• Blood also contains white blood cells. They are colorless and do not contain hemoglobin.

• Also called leukocytes. (leuko-white)

• They are bigger than red blood cells and have large nuclei.

• Act as the body’s defense system.

• It can move, change its shape and squeeze through the walls of the fine blood capillaries into the space among the tissue cells.

• Begin developing in the bone marrow and mature in the lymph organs and nodes

• Some white blood cells surround and consume harmful microbes.

• Some produce chemicals called antibodies that fight infection.

Blood Platelets or Thrombocytes

• Platelets are also carried in the blood. They are not true cells but are fragments of cytoplasm large bone marrow cells known as megakaryocytes.

• Formed in red bone marrow.

• Produce thrombokinase – a chemical needed for blood clotting.

• Platelets help to repair tissues and close wounds both internally and externally.

• When needed, they grow into irregular shapes and stick together to form a plug over the wound.

Plasma

• The blood cells and platelets are suspended in a substance called plasma. It is a pale yellowish liquid that is 92% water

• Soluble or plasma proteins(serum globulin, fibrinogen, antibodies)

VASODILATION

• Body gets too hot, capillaries near the surface of the skin widen. Blood is diverted to the skin where the heat can easily radiate away.