No there are no vacuoles in a human but there are in a plant but not humans.
Answer:
B. Shortens
Explanation:
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
Some scientists hypothesize that the eukaryotic cells are really the result of symbiotic processes!
Specifically, the internal organs of the cells could be a remnant of a symbiotic relationship in which one cell lived inside of another cell. These two cells then both split upon reproduction and eventually the cell inside was reduced to an organelle.
But according to this theory, it is very likely that the prokaryotic cells engaged in a number of symbiotic relationship, and that this actually lead to the emergence of eukaryotic cells!
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I think it's <span>a=F/m ; F=m/a=1200 kg x 3.0 m/s^2 = 3600 N</span>
