Question

4p When a sarcomere contracts, the dark band gets wider O the dark band gets narrower O the light band gets wider o the light band gets narrower O Z disks do not move

Answer 1

ANSWER

Q.1 - Option D is correct

• When a sarcomere contract the LIGHT band get narrower.
• A sarcomere is the basic contractile unit of muscle fiber.
• sarcomerecomposed of 2 main protein ie, actin and myosin which are the active structures responsible for muscular contraction.
• ACTIN give thin BAND and called I-BAND
• MYOSIN give thick BAND and called A-BAND

Q.2 - Option A is correct

• Homology- Homology is the similarities between the organisms due to common ancestors based on genes, physiology or development.
• here, forelimbs of vertebrates, where the wings of birds, the arms of primates, the front flippers of whales and crocodiles are all derived from the same ancestral Tetrapoda