Date | November 2019 | Marks available | 3 | Reference code | 19N.3.HL.TZ0.21 |
Level | Higher level | Paper | Paper 3 | Time zone | TZ0 / no time zone |
Command term | Explain | Question number | 21 | Adapted from | N/A |
Question
The figure below shows the average death rates from coronary heart disease in the UK.
[Source: Bhatnagar P, Wickramasinghe K, Wilkins E, et al, Trends in the epidemiology
of cardiovascular disease in the UK, Heart 2016; 102: 1945–1952.]
Suggest one reason for the general decrease in the incidence of coronary heart disease.
Outline the use of a defibrillator.
Explain the heart sounds.
Markscheme
improvement in medical care Accept improvements in medication.
OR
healthier diet
OR
decrease in blood cholesterol/pressure
OR
decrease in cigarette smoking
OR
increase in exercise ✔
Accept other answers relating to greater awareness about health issues.
a. used in life-threatening cardiac conditions/arrythmia/ventricular fibrillation ✔
b. delivers therapeutic/small dose/shock of electrical energy ✔
c. depolarizes the heart muscle
OR
allows normal rhythm to be re-established ✔
a. «heart sounds» produced by the closing of the valves ✔
b. first sound «lub» is due to «closure of» the atrioventricular valves ✔ Accept bicuspid/mitral and tricuspid.
c. second sound «dub» is due to «closure of» the semilunar valves ✔ Accept pulmonary/aortic valves.
d. sequence of sounds from a healthy heart is lub dub «pause lub dub pause» ✔ OWTTE