PHYSIOLOGY
SKELETAL MUSCLE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
In a relaxed muscle, the H zone is at its narrowest width
|
|
True
|
|
|
False
|
|
|
Either A or B
|
|
|
None of the above
|
Explanation:
Detailed explanation-1: -In a contracting muscle the Z lines come closer together. In a relaxed muscle, the H zone is at its narrowest width.
Detailed explanation-2: -The H zone-the central region of the A zone-contains only thick filaments (myosin) and is shortened during contraction. The H zone becomes smaller and smaller due to the increasing overlap of actin and myosin filaments, and the muscle shortens.
Detailed explanation-3: -H-band is the zone of the thick filaments that has no actin. Within the H-zone is a thin M-line (from the German “mittel” meaning middle), appears in the middle of the sarcomere formed of cross-connecting elements of the cytoskeleton.
There is 1 question to complete.