Blood vessels

The diagram shows the human circulatory system, with blood vessels labelled A to N.

The table lists some of the blood vessels in the human circulatory system. Complete the table by giving the correct letter for each blood vessel. The first one has been done for you.

Use letters from the diagram to answer these questions.

Which blood vessel contains blood with the highest concentration of oxygen?

Which blood vessel carries blood at the highest pressure?

Which blood vessel is an artery that carries blood with a high concentration of carbon dioxide?

Scientists have developed a synthetic material that can be used to replace damaged arteries. State two properties that this synthetic material should have so that it can act as a suitable replacement for damaged arteries.

Blood is circulated through the body in blood vessels.

The table lists some blood vessels. Complete the table by naming an organ supplied with blood by each blood vessel.

A student uses this apparatus to compare the strength of arteries and veins.

This is the student’s method.

• cut a cross-section from an artery and from a vein to make rings of tissue

• hang a ring of tissue from the hook

• add 10 g masses to the ring of tissue one at a time

• record the total mass at which the ring of tissue breaks

• repeat the method with the other ring of tissue

Explain the results that you would expect the student to obtain.

Give one way that the student could modify his investigation to improve the reliability of his results.

Give one way that the student could modify his investigation to improve the accuracy of his results.

Chemotherapy is often used to help people with cancer. Chemotherapy kills cancer cells but may affect haemoglobin production in the body. A drug called EPO increases haemoglobin production in the body. Scientists investigated the effect of EPO on patients who had received chemotherapy. They injected EPO into these patients and blood samples were taken for several months to measure their haemoglobin levels. The table shows the results.

Plot a line graph to show the relationship between time and average haemoglobin level. Use a ruler to join the points with straight lines.

Name the dependent variable in this investigation.

Explain how the scientists made sure their results were reliable.

The scientists controlled biotic (living) factors so their results would be valid. Name two biotic factors that the scientists should have controlled.

Cancer patients often complain of tiredness after chemotherapy. Explain how EPO helps to reduce tiredness in these patients.

The scientists obtained blood samples using a needle attached to a syringe. Explain which type of blood vessel they should use to obtain the blood samples.

The diagrams show sections through an artery and a vein.

Use the information in the diagrams and your own knowledge to give three ways in which the structure of an artery differs from the structure of a vein.

Lack of movement by sitting still for long periods of time makes blood flow very slowly in a vein. Blood that flows slowly is more likely to clot than blood that flows normally. This problem is known as deep vein thrombosis (DVT). In DVT, the clot usually occurs in a leg vein as shown in the diagram.

DVT is dangerous because sometimes part of the clot breaks off and travels to the lung, blocking small blood vessels and causing death.

Suggest why blood flow in a leg vein is slow when there is lack of movement.

Name the blood cells responsible for transporting oxygen.

Suggest why a clot that blocks the small blood vessels in the lungs can cause death.

The diagram shows some of the blood vessels and a nephron in the human kidney. The numbers represent the concentration of glucose at various places in the blood vessels and in the nephron, in arbitrary units.

Explain how the structure of the blood vessels entering and leaving the glomerulus help to move glucose into the Bowman’s capsule.

What type of blood vessels are found in the glomerulus?

Describe how glucose is reabsorbed from the nephron back into the blood.

Suggest why glucose needs to be returned to the blood.