Across
- 4. A compound that can maintain a constant pH
- 5. Chambers located at the top of the heart
- 8. Specialised muscle fibres that conduct electrical impulses
- 10. The result of oxygen and haemoglobin
- 15. Prevents valves from turning inside out
- 17. A type of white blood cell activated as part of the immune system
- 18. Caused by restricted blood flow to the heart
- 19. The stage of the heart cycle in which heart muscle must contract to pump blood
- 20. red fluid that flows through our bodies
- 22. Red blood cells
Down
- 1. Inefficient pumping of the heart
- 2. Tissue that lines the inside of a blood vessel
- 3. An attraction
- 6. The patch of tissue that initiates the heart beat
- 7. The wall that separates the atria from the ventricles
- 8. The concentration of oxygen
- 9. Small air sacs in the lungs
- 11. The term that states that the heart can cause its own electrical impulses
- 12. The effect of carbon dioxide concentration on the affinity of haemoglobin for oxygen
- 13. A structural fibrous protein
- 14. Allows red blood cells to have a larger surface area
- 16. The sequence of events making up one heart beat
- 21. Oxyhaemoglobin must release oxygen for this to happen
- 23. This bathes the cells of individual tissues