The circulatory system is responsible for transporting oxygen and nutrients around the body.
Describe three structural features of capillaries that adapt them for the rapid and efficient exchange of substances with surrounding tissues.
Coronary heart disease (CHD) is a condition where fatty deposits build up inside the coronary arteries, narrowing their lumen. Explain how this structural change reduces the rate of blood flow to the heart muscle, and how the resulting lower oxygen delivery affects the heart muscle cells' respiration and performance during physical exertion.
Practise AQA GCSE Biology 2.2 Animal tissues, organs and organ systems with exam-style questions for Foundation and Higher tier. 70 questions covering 2.2.1 The human digestive system, 2.2.2 The heart and blood vessels, 2.2.3 Blood, 2.2.4 Coronary heart disease: a non-communicable disease, 2.2.5 Health issues, 2.2.6 The effect of lifestyle on some non-communicable diseases, and 2.2.7 Cancer, matched to the AQA GCSE Biology (8461) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.