| Date | May 2010 | Marks available | 1 | Reference code | 10M.1.HL.TZ2.21 |
| Level | Higher level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | State | Question number | 21 | Adapted from | N/A |
Question
What is a role of the pacemaker or sinoatrial node (SAN)?
A. To initiate contraction of the ventricle
B. To pass the excitation through Purkinje fibres
C. To originate excitation in myogenic muscle
D. To cause the relaxation of the atria
Markscheme
C
Examiners report
N/A
Syllabus sections
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