Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Remote ischemic conditioning wikipedia , lookup
Heart failure wikipedia , lookup
Cardiac contractility modulation wikipedia , lookup
Mitral insufficiency wikipedia , lookup
Antihypertensive drug wikipedia , lookup
Cardiac surgery wikipedia , lookup
Myocardial infarction wikipedia , lookup
Hypertrophic cardiomyopathy wikipedia , lookup
Coronary artery disease wikipedia , lookup
Management of acute coronary syndrome wikipedia , lookup
Arrhythmogenic right ventricular dysplasia wikipedia , lookup
HL Biology 1. H5 - Transport One type of heart disease is diastolic heart failure (DHF). A study was carried out to see if DHF was related to abnormalities in the diastolic properties of the left ventricle. Two groups of patients, one with DHF and the other the control group with no symptoms of DHF, were assessed to compare: changes in left ventricular diastolic pressure and volume and stiffness of muscles leading to resistance of the left ventricle to stretch under increasing pressure. Graph 1 shows the mean lowest pressure in the left ventricle during diastole after the opening of the atrio-ventricular valve. Graph 2 shows individual stiffness constants. M R Zile et al., “Diastolic heart failure: Abnormalities in active relaxation and passive stiffness of the left ventricle”, New England Journal of Medicine (2004), vol. 350, issue 19, pp. 1953–1959. Copyright ©1994 Massachusetts Medical Society. All rights reserved 1 HL Biology (a) H5 - Transport Identify the left ventricular diastolic volumes in patients and the control group that correspond to a pressure of 5 mm Hg. Patients: ........................................................................................................ Control group: ........................................................................................................ (1) (b) Compare the diastolic pressure-volume relationship of patients with DHF and the control group. .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (2) (c) Distinguish between the stiffness constants in the two groups of patients. .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (1) (d) (i) Suggest why in patients with DHF there is little or no increase in blood volume pumped out of the left ventricle with each contraction during exercise. ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... (1) 2 HL Biology H5 - Transport (ii) Deduce how patients with DHF would respond to heavy exercise. ........................................................................................................................... ........................................................................................................................... (1) (Total 6 marks) 2. Poor nutrition of a woman during pregnancy has been associated with a variety of metabolic disorders later in the life of her offspring. During the second world war (WWII) the normally well-fed population of Holland suffered famine over a relatively short and precisely defined period. The data available from this period provided examples of fetuses that were affected by famine at specific periods during pregnancy. Glucose tolerance was analysed in human adults 50–55 years of age who had suffered fetal famine during WWII (Figure 1). High glucose levels in blood plasma indicate poor glucose tolerance. Figure1: Glucosetolerance Plasmaglucose concentration/ mmol 1–1 6.4 6.3 6.2 6.1 6.0 5.9 5.8 5.7 5.6 5.5 5.4 Born before famine Late pregnancy M id pregnancy Early pregnancy Conceived after famine Periodof exposuretofamine [Source: N Metcalfe and P Monaghan, (2001), Trends in Ecology and Evolution, 16, pages 254-260] (a) (i) Identify the period of exposure to famine that produces the greatest decrease in glucose tolerance. ........................................................................................................................... (1) 3 HL Biology H5 - Transport (ii) Calculate the percentage change in plasma glucose concentration after exposure to famine from early to late pregnancy. ........................................................................................................................... ........................................................................................................................... (1) (iii) Suggest a reason why glucose tolerance did not return to normal in people conceived after the famine. ........................................................................................................................... ........................................................................................................................... (1) (b) Outline a possible cause of poor glucose tolerance. ..................................................................................................................................... ..................................................................................................................................... (1) (c) Suggest how poor glucose tolerance could be related to the occurrence of coronary heart disease. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (Total 6 marks) 4 HL Biology 3. (a) H5 - Transport Distinguish between the mode of action of steroid and protein hormones. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (b) Explain the events of the cardiac cycle including systole, diastole and heart sounds. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (6) (Total 8 marks) 5 HL Biology 4. H5 - Transport Discuss factors which affect the occurrence of coronary heart disease. ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... (Total 7 marks) 6