Anatomy Of The Heart Worksheet With Answers (Page 4 of 5) in pdf

Anatomy Of The Heart Worksheet With Answers Page 4

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M i c r o s c o p i c A n a t o m y o f C a r d i a c M u s c l e

Both tissue types are stri-

13. How would you distinguish the structure of cardiac muscle from the structure of skeletal muscle?

ated; thus, this is not a distinguishing feature. Skeletal muscle cells are long cylindrical cells with many nuclei per cell. Cardiac cells

have one (or two) centrally located nuclei per cell; their branched ends fit together at tight junctions called intercalated discs, which

are not seen in skeletal muscle.

14. Add the following terms to the photo

of cardiac muscle at the right:

intercalated disc

b. nucleus of cardiac fiber

striations

d. cardiac muscle fiber

15. What role does the unique structure of cardiac muscle play in its function? (Note: Before attempting a response, describe the

Cardiac muscle cells form a functional syncytium by virtue of their intercalated discs. This structural feature plus

unique anatomy.)

the special arrangement of cardiac muscle in the heart allows the pumping action of the heart to be carefully coordinated for maximal

efficiency.

D i s s e c t i o n o f t h e S h e e p H e a r t

16. During the sheep heart dissection, you were asked initially to identify the right and left ventricles without cutting into the

heart. During this procedure, what differences did you observe between the two chambers?

The left ventricle was firmer, thicker, and less compressible; the right ventricle felt “flabby.”

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Review Sheet 30

Anatomy Of The Heart Worksheet With Answers Page 4