CSEC Human and Social Biology · May/June 2009 · Paper 2 · Question 14(c)(i)
Cardiac cycle, pulse, and regulation.
State the function of the pacemaker in the heart.
The mark scheme is shown once you've answered.
Practise this questionOther parts of this question
- 14(a)Identify the parts labelled A, B, C, D, and E in Figure 5 showing the heart and major blood vessels.[5 marks]
- 14(b)Explain how the heart functions as a double pump.[4 marks]
- 14(c)(ii)State the number of heart beats in one minute for an individual with a pulse rate of 72.[1 mark]
- 14(c)(iii)Suggest TWO reasons why an individual's pulse rate may increase after lunch (e.g. from 72 to 82).[2 marks]
- 14(d)(i)Suggest ONE possible cause of atherosclerosis as illustrated in Figure 6.[1 mark]
- 14(d)(ii)State the effect that narrowed arteries with atherosclerosis have on blood pressure.[1 mark]
- 14(d)(iii)Identify ONE difference in structure between an artery and a vein other than the thickness of the muscular wall.[1 mark]
- 14(e)Explain how vasodilation and vasoconstriction of skin blood vessels regulate body temperature.[4 marks]
More practice: the rest of this paper · more The Circulatory and Lymphatic Systems questions · all CSEC Human and Social Biology past papers