Date | November 2021 | Marks available | 1 | Reference code | 21N.1.HL.TZ1.24 |
Level | Higher level | Paper | Paper 1 | Time zone | Time zone 1 |
Command term | Question number | 24 | Adapted from | N/A |
Question
The image shows the four chambers of the mammalian heart viewed from the ventral side. The sinoatrial node is located in the wall of one of these chambers. Which chamber is it?
[Source: Anatomy Corner, n.d. [Elk heart]. [image online] Available at: http://anatomycorner.com/main/image-gallery/elk-heart/
[Accessed 23 March 2020].]
Markscheme
A
Examiners report
The last skill in sub-topic 6.2 was the basis for this question. Students are expected to identify chambers and blood vessels of the heart from dissected hearts, images of photographs of hearts or diagrams of heart structure. A G2 comment was made that the term ‘ventral’ may have been unfamiliar to students and that ‘front view’ would have been better. This wasn’t a human heart so the term ‘front view’ would be ambiguous. What is the front view of a sheep? The terms dorsal and ventral are useful when studying bilaterians and ideally students should become familiar with them. Also identifying parts of the heart in a photo of a heart or a real specimen is a much more useful skill than identifying them in a diagram, where they are very likely already to be labelled.