Muscle and muscle tissue

Question 1

How can we defer (or reverse) some of the effects of age on skeletal muscles?

Answer 1

regular exercise and strength training help to defer the loss in strength and muscle wasting that tends to occur with age and improve neuromuscular function.

Question 2

what does it mean when we say muscles get stringier with age?

Answer 2

The connective tissue in muscles increases with age, causing the muscles to get stringier.

Question 3

how is the multinucleated condition achieved during development of skeletal muscle fibers?

Answer 3

During development of skeletal muscle fibers, the myoblast cells join together, forming multinucleate myotubes.

Question 4

How does the stress-relaxation response suit the role of smooth muscle in hollow organs?

Answer 4

Hollow organs that have smooth muscle cells helping to form their walls often must temporarily store the organs content (urine,food residues,etc.) an ability ensured by stress- relaxation response.

Question 5

Calcium is the trigger for contraction of all muscle types. How does its binding site differ in skeletal and smooth muscle fibers?

Answer 5

Calcium binds to troponin on the thin filaments in skeletal muscle cells. In smooth muscle cells, it binds to a cytoplasmic protein called calmodulin.

Question 6

Compare the structures of skeletal and smooth muscle fibers.

Answer 6

Both skeletal and smooth muscle fibers are elongated cells, but unlike smooth muscle cells, which are spindle shaped, uninucleate, and nonstriated, skeletal muscle cells are very large cigar-shaped, multinucleated, striated cells.