Atherosclerosis, blood clotting and cardiovascular diseaseEdexcel A-Level Biology A: Subtopic test

1. 1
   A 58-year-old man is told that he has atherosclerosis in his coronary arteries. His doctor explains that it develops slowly over many years and often begins when the lining of an artery is damaged.

   (a)

   Which part of an artery is damaged first in the development of atherosclerosis?

   [1 mark]

   • AThe outer layer of collagen fibres
   • BThe layer of elastic fibres
   • CThe red blood cells in the lumen
   • DThe endothelium

   (b)

   Which cells move into the artery wall as part of the inflammatory response in atherosclerosis?

   [1 mark]

   • ARed blood cells
   • BNeurones
   • CWhite blood cells
   • DHepatocytes

   (c)

   Explain how atherosclerosis can lead to raised blood pressure.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A woman cuts her finger on a knife. The wound bleeds for a short time and then a clot forms and stops the bleeding within a few minutes.

   (a)

   Which protein in the blood plasma is converted into thrombin?

   [1 mark]

   • AProthrombin
   • BFibrinogen
   • CHaemoglobin
   • DAlbumin

   (b)

   Which substance forms the mesh of fibres that traps red blood cells in a blood clot?

   [1 mark]

   • AFibrinogen
   • BThrombin
   • CThromboplastin
   • DFibrin

   (c)

   Describe the role of thrombin in the formation of a blood clot.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A 62-year-old man has had high blood pressure for many years and has atherosclerosis in one of his coronary arteries. One day a plaque in this artery ruptures and a blood clot forms that blocks the artery completely. He has a myocardial infarction (heart attack).

   (a)

   Explain how long-term high blood pressure can lead to the development of atherosclerosis, and how atherosclerosis can in turn raise blood pressure further.

   [3 marks]

   (b)

   Explain how the blocked coronary artery caused damage to the man's heart muscle.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   Cardiovascular disease is a leading cause of death in the UK. A medical student is preparing a presentation on how atherosclerosis develops and how it can lead to a heart attack or a stroke.

   (a)

   Describe the course of events that leads to atherosclerosis.

   [6 marks]

   (b)

   Explain how atherosclerosis and the blood clotting process can combine to cause a myocardial infarction or a stroke.

   [6 marks]

   Total for question 4: 12 marks

End of questions