Cardiac Muscle
Across
- 1. The third wave is a dome-shaped upward deflection called the
- 4. Cardiac excitation normally begins here
- 8. The mechanism of contraction is similar in cardiac muscle is similar to ________ muscle
- 13. This is a period of maintained depolarization in contractile fibre
- 14. This is a small upward deflection on the ECG
- 15. This cell organelle is larger and more numerous in cardiac muscle fibers than in skeletal muscle fibers.
- 17. These large diameter fibres rapidly conduct the action potential beginning at the apex of the heart upward to the remainder of the ventricular myocardium
- 18. __________ Q wave may indicate a myocardial infarction
- 20. The instrument used to record the changes is called
- 21. The recovery of the resting membrane potential takes place during this phase of action potential
- 23. cardiac muscle has a smaller intracellular reserve of ______ ions
- 24. QRS complex begins with a ________ deflection
- 25. ECG involves measuring the time spans between waves called
- 27. The spontaneous depolarization in SA node is a ______ potential
- 28. AV bundle is also called as
- 29. The phase of relaxation.
Down
- 2. A recording of electrical signals is called
- 3. High blood K+ level causes
- 5. Intercalated discs contain these to hold the fibres and gap junctions together.
- 6. Larger P waves indicate enlargement of
- 7. irregular transverse thickenings of the sarcolemma are called
- 9. The SA node is a ______ pacemaker
- 10. First step in the action potential occurs of a contractile fiber
- 11. This sets the rhythm of electrical excitation that causes contraction of the heart.
- 12. The source of this electrical activity is a network of specialized cardiac muscle fibers called
- 16. the action potential travels along the conduction system and spreads out to excite these fibres
- 19. These allow the entire myocardium of the atria or the ventricles to contract as a single, coordinated unit.
- 21. In muscle, this period is the time interval during which a second contraction cannot be triggered
- 22. the phase of contraction
- 26. Number nuclei present in a muscle cell