Muscle Flashcards

1
Q

sarcomere

A
  • composed of overlapping filaments of actin and myosin as well as structural and binding proteins (eg, titin, α-actinin).
  • single sarcomere is defined as the distance between two Z lines.
  • Thin (actin) filaments are bound to structural proteins at the Z line.
  • The unbound ends of the actin filaments project into the middle of the sarcomere, where they interact with thick (myosin) filaments during muscle contraction.
  • Myosin and actin filaments overlap at the segment of the sarcomere between the H and I bands.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

A band

A
  • myosin filaments in the sarcomere
  • In this region, there are myosin filaments overlapped with actin filaments as well as non-overlapped myosin filaments.
  • always remains the same length during muscle contraction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

M line

A

lies at the center of the A band and is where myosin filaments anchor to structural elements in the center of the sarcomere.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

I band and H band

A
  • I band is the region of the sarcomere in which actin does not overlap with myosin
  • H band is the region in which myosin does not overlap with actin.
  • During muscle contraction, both H and I bands decrease in length.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly