2 organisation - the heart

Question 1

4 chambers of the heart

Answer 1

• right atrium
• right ventricle
• left atrium
• left ventricle

Question 2

5 steps of blood flow through the heart

Answer 2

1. blood flows into the two atria from the vena cava and pulmonary vein
2. atria contract - pushing blood into ventricles
3. ventricles contract pushing blood into the pulmonary artery and aorta out of the heart
4. then blood flows to the organs through arteries/veins/capillaries
5. atria fill and cycle restarts

Question 3

2 key points of the double circulatory system

Answer 3

1. right ventricle pumps DEOXYGENATED blood to lungs to take in oxygen and then returns to the heart
2. left ventricle prumps oxygenated blood to other organs in body

Question 4

arteries

Answer 4

• high-pressure blood
• away from the heart
• stick/ strong/ elastic walls
• muscle walls

Question 5

capillaries

Answer 5

• arteries branch into capillaries
• carry blood close to every cell to exchange substances with them
• permeable walls to supply food and oxygen and take away co2 and waste
• one cell thick walls - increases rate of diffusion

Question 6

veins

Answer 6

• join with capillaries to take blood TOWARDS the heart
• thin walls bc low pressure
• large lumen to help flow
• valves - stop backflow of blood