Question

starting from and ending with the right atrium, trace the flow of blood through the heart and body by numbering each stage in the correct order.
right atrium
left atrium
pulmonary artery
vena cava
aorta
lungs
right ventricle
left ventricle
body cells
pulmonary veins
starting from and ending with the heart, trace the flow of blood through the human circulatory system and body by numbering each stage in the correct order.
heart
veins
arterioles
capillaries
arteries
venules

Explanation:

For the first part:

• Deoxygenated blood from the body enters the right atrium (1).
• It then goes to the right ventricle (2), which pumps it to the lungs via the pulmonary artery (3).
• In the lungs (4), blood gets oxygenated and returns via pulmonary veins (5) to the left atrium (6).
• From the left atrium, blood moves to the left ventricle (7), which pumps it through the aorta (8) to the body cells (9).
• Deoxygenated blood from body cells returns to the heart via the vena cava (10) to the right atrium.

For the second part:

• The heart (1) pumps blood into arteries (2).
• Arteries branch into arterioles (3), which further branch into capillaries (4) for gas and nutrient exchange.
• Capillaries merge into venules (5), which then form veins (6) that return blood to the heart.

Answer:

For the first part (blood flow through heart and body starting and ending with right atrium):

1. right atrium
2. right ventricle
3. pulmonary artery
4. lungs
5. pulmonary veins
6. left atrium
7. left ventricle
8. aorta
9. body cells
10. vena cava

For the second part (blood flow through human circulatory system and body starting and ending with heart):

1. heart
2. arteries
3. arterioles
4. capillaries
5. venules
6. veins