Lesson 12: Blood flowLesson 12: Blood flowObjective:-Heart’s and body’s blood supply-Components of blood

http://www.britannica.com/EBchecked/topic/95628/human-cardiovascular-system/33561/Blood-supply-to-the-heart

Coronary Blood supplyCoronary Blood supplyThere are two main coronary arteries: the

left main coronary artery and the right coronary artery which come from the aorta.

The left main coronary artery divides into the left anterior descending branch and the left circumflex arteries.

Each artery supplies blood to different parts of the heart muscle and the electrical system.

BloodBloodPlasma: Pale liquid that carries all the

other parts of the blood, nutrients, CO2, urea, hormones and antibodies

White blood cells: Defends against disease, make antibodies and antitoxins

Platelets: Have no nucleus, help clot bleeding

Red Blood Cells: Carry Oxygen and iron. They have no nucleus

Parts of the Circulatory Parts of the Circulatory SystemSystem

Arteries: - carry oxygenated blood away from the

heart- Leaves the heart at high pressure, so

the walls are thick, strong and elastic- Narrower “lumen” or canal- EXCEPTION: pulmonary arteryCapillaries:- Are very small, one cell thick - Diffuse food and oxygen to body tissues- Take CO2 and urea away from body

tissues

Veins- Take blood back to heart- Blood has lower pressure so the

walls are thinner- Larger “lumen” or tube to carry the

blood- Have valves to keep the blood

flowing in the right direction- EXCEPTION: pulmonary vein

MicroscopesMicroscopes

Start at one of the microscopes. Observe the slide, write down the stations’ number and what you are observing. After 2 minutes rotate clockwise until you have seen all of the slides.

HomeworkHomework

Crossword and question sheet