Across
- 6. Impulses from the cerebrum or ______________ may influence heart rate through emotions.
- 8. The flow of blood when the left ventricle contracts.
- 11. An abnormal rate (less than 60 beats/min).
- 12. Systolic blood pressure is exerted on the atrial walls when.
- 14. The tissue that forms the lining on the surface of the heart.
- 15. The region in the middle of the thoracic cavity that is occupied by the heart, great vessels, thymus, and trachea.
Down
- 1. The tissue that forms the middle and thickest layer of the heart.
- 2. The valve that prevents backwards flow into the left atrium
- 3. Oxygen rich blood is carried by this circuit.
- 4. A condition in which there is an increase in K+ which decreases heart rate and force of contraction.
- 5. Depolarization of atrial muscle fibers.
- 7. An abnormal rate (more that 100 beats/min.
- 9. A condition in which there is an increase in Ca+2 which increase heart action.
- 10. The tissue that forms the inner layer that contains Purkinje fibers of the heart
- 12. The "lubb" sound of the heart is caused when which valves close
- 13. Polarization of the ventricular muscle fibers.