| Date | May 2019 | Marks available | 1 | Reference code | 19M.2.HL:.tz0.4 |
| Level | Higher Level | Paper | Paper 2 | Time zone | time zone 0 |
| Command term | Define | Question number | 4 | Adapted from | N/A |
Question
Define systolic blood pressure.
Predict the effect of a 100 m sprint on a runner’s systolic and diastolic blood pressure.
Explain the redistribution of blood during exercise.
Markscheme
the force exerted by blood on arterial walls during ventricular contraction ✔
[1]
increase in systolic blood pressure ✔
no change/slight decrease in diastolic blood pressure ✔
[2]
(vaso)dilation of blood vessels/arterioles to «working» muscle/(vaso)constriction of blood vessels/arterioles to non-working muscles
OR
shunting of blood to working muscles/away from non-essential tissues ✔
increased blood flow to the working muscles «by 25 times»
OR
approximately 80–85% of cardiac output is directed to «working» muscles / 15–20% blood flow to non-working muscles ✔
brain receives approximately the same volume of blood during rest and exercise ✔
increased blood in working muscles improves transport/delivery of oxygen ✔
increased blood in working muscles aids waste product removal ✔
[3 max]
Examiners report
Too many students were not able to define systolic blood pressure well.
Generally the students were able to identify what happened to systolic blood pressure but were often vague or incorrect in their responses regarding the diastolic blood pressure.
Too many candidates were able to only state that the blood is redistributed to the working muscles because of the increased need for oxygen. Many candidates showed little to no understanding of the process.
