Circulatory system components

Nota:

• Arteries: carry blood from heart to the rest of the body. They have strong muscular walls. Veins: carry blood from the rest of the body to the heart. They have elastic walls Capillaries: allows substances to pass through cells or viceversa. They are very thin

1. Arteries

   Nota:

   • Blood in the arteries is under high pressure generated by the heart. The arteries have: 1.thick outer walls 2. thick layers of muscle and elastic fibres.
2. Veins

   Nota:

   • The blood in veins is under lower pressure than the blood in arteries. The veins have: 1. thin walls 2. thin layers of muscle and elastic fibres.3. Unlike arteries, veins have one-way valves in them to keep the blood moving in the correct direction.
3. Capillaries

   Nota:

   • The function of capillaries is to allow food and oxygen to diffuse to cells while waste is diffused from cells. Capillaries have thin walls - only one cell thick 

Nota:

• It transports: nutrients, oxygen, CO2, waste products (urea), hormones, etc.

1. Plasma
2. RBC
3. WBC
4. Platelets
5. Blood composition

Nota:

• Pumps blood to different parts of the body

1. 4Chambers
2. Septum
3. Valves
4. Circulation