Answer:
I'm not 100% sure but I think it either a or d
Explanation:
hope this helps
So following the octet rule, carbon atom can only form a maximum of 4 bonds because, by then, it will have 8 valence electrons.
Each myofibril is attached at either end of the muscle fiber, when sarcomeres shorten, the muscle fiber Shortens
Mechanism :
Myofibrils are components of the animal skeletal muscles that are made up of sacromeres. They perform the muscular contraction and relaxation via the sliding filament model.
To produce motion, A cross-bridge forms between actin and the myosin heads triggering shortening of the sacromere. This shortening of the sacromere results in the contraction of the muscle fibers, which the net effect can be seen to be a shortening of the fibers.
To learn more about myofibril refer to : brainly.com/question/15461128
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