The natural resting heart rate is controlled by a group of cells that act as a pacemaker.
Name the part of the heart in which these cells are found.
Describe how these cells control the heartbeat.
A person's natural pacemaker stops working properly and their heartbeat becomes irregular. Give one way in which this could be treated.
179 exam-style questions on AQA GCSE Biology 2.2 Animal tissues, organs and organ systems, 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. Each one has a worked solution and a mark scheme showing where the marks go.