Answer:
1.All living things are composed of cells.
2.Cells are the basic units of structure and function for living things.
3.All cells come from pre-existing cells. Also, organisms grow by “adding on more cells” NOT by increasing the size of their cells.
Yes, It indeed is inside a cell's nuculeus. You are correct
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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