Across
- 2. 2nd most numerous WBC
- 5. the inner layer of the heart
- 8. microscopic 1 cell thick vessels
- 10. valve located between the left atrium and left ventricle
- 11. stopes the backflow into the chambers of the heart
- 15. a reaction which particles suspend in a liquid collection into clumps
- 17. a process in which WBC surround, engulfs and destroys a pathogen
- 18. media middle layer of a blood vessel
- 19. arising from the left ventricle
- 20. the wall separating the heart into left and right sides
- 21. ventricle the left lower side of the heart
Down
- 1. iron containing pigment in RBC
- 3. most numerous WBC with adults
- 4. rapid uncoordinated contractions
- 6. the smallest branch of arteries
- 7. the smallest of veins
- 9. the fluid filled sac surrounding the heart
- 12. top layer of clear fluid
- 13. the lower pumping chamber of the heart
- 14. the contracting phase of the heart
- 16. the inner space of a blood vessel