6.3 Microscopic Anatomy of Skeletal Muscle

Question 1

What are the functions of muscle?

Answer 1

• Produce movement
• Maintain posture
• Stabilize joints
• Generate heat
• Additional fxn:
- smooth: valves, dilation/constriction of pupils, arrector pili
- skeletal: valves (conscious control)

Question 2

Cells are ______?

Answer 2

Multinucleate

Question 3

Where is the nuclei located in the microscopic anatomy of skeletal muscle?

Answer 3

Nuclei are just beneath the sarcolemma.

Question 4

What is the contractile unit of a muscle fiber?

Answer 4

Sarcomere

Question 5

What are these bundles of myofilament?

Answer 5

Myofibril

Question 6

What is the specialized plasma membrane?

Answer 6

Sarcolemma

Question 7

What is the specialize smooth endoplasmic reticulum?

Answer 7

Sarcoplasmic Reticulum

Question 8

What is the name for the light band?

Answer 8

I Band

Question 9

What is the name for the dark band?

Answer 9

A Band

Question 10

What is the thick filament called?

Answer 10

Myosin

Question 11

What is the thin filament called?

Answer 11

Actin

Question 12

What filaments have heads (extensions, or cross bridges)?

Answer 12

Myosin