This definitions covers Key Definitions within The Heart and Circulation for GCSE Biology. Heart structure, cardiac cycle, blood vessels, double circulation, heart rate control, and cardiovascular health It is section 9 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Topic position
Section 9 of 14
Practice
20 questions
Recall
25 flashcards
Key Definitions
Atrium (plural: atria): The upper chambers of the heart that receive blood returning from the body (right atrium) or lungs (left atrium).
Ventricle: The lower, more muscular chambers of the heart that pump blood out — right ventricle to lungs, left ventricle to body.
Valve: A flap in the heart or veins that prevents the backflow of blood; ensures blood moves in one direction only.
Coronary artery: Blood vessels that supply the heart muscle itself with oxygenated blood; blockage leads to a heart attack.
Cardiac output: The volume of blood pumped by the heart per minute; calculated as heart rate multiplied by stroke volume.
Double circulation: The mammalian system in which blood passes through the heart twice for each complete circuit of the body — once for pulmonary circulation (heart to lungs and back) and once for systemic circulation (heart to body and back).