Question

1. Identify Figures A and B.
2. Label X, Y and Z.
3. Which acts as an impulse booster?
4. Which is under voluntary control?

Answer 1

1. A - cardiac muscle fibres; B - skeletal (striated) muscle fibres.
2. X - intercalated disc; Y - light band; Z - dark band.
3. The intercalated disc acts as an impulse booster.
4. Skeletal (striated) muscle is under voluntary control.