B2.2.3

Question 1

What type of muscle is the heart made out of

Answer 1

Your heart is made out of cardiac muscles a type of muscle and found in the heart. Cardiac muscle cells contract without receiving a nerve impulse from your brain. Many cells contract together to produce a heartbeat.

Question 2

What does the heart contain

Answer 2

Your heart contains four chambers. The two smaller chambers at the top are called atria. The two larger chambers at the bottom are called ventricles. Valves separate chambers.

Question 3

What is the flow of blood through the heart

Answer 3

Deoxygenated blood enters the right atrium from the vena cava. It is then pumped into the right ventricle when the heart beats. From here it is pumped to the lungs through the pulmonary artery to collect oxygen. The blood returns to the heart (via the pulmonary vein) into the left atrium. It is then pumped into the left ventricle. The muscle in the left ventricle has to be very thick, to pump blood at high pressure through the aorta. Makes blood travel around the whole body.

Question 4

What are red blood cells

Answer 4

Small biconcave cells that have no nucleus and contain haemoglobin. They carry oxygen. They fit through the lumen of the capillary one cell at a time.

Question 5

What are white blood cells

Answer 5

Large cells contain a nucleus. They fight disease by making antibodies, or by changing shape to engulf microorganisms.

Question 6

What are platelets

Answer 6

Tiny structures that help blood to clot

Question 7

Plasma

Answer 7

Straw coloured liquid that blood cells float in. 90% of plasma in water. These included digested food, waste, and antibodies.