Answer:
Because enzymes have many functions as chemical catalysts in numerous chemical reactions (for example in metabolism). By lowering the activation energy, they make it much easier to carry out reactions. They are also indispensable for signal transduction and cell regulation, often via kinases and phosphatases. They also generate movement, with myosin hydrolyzing ATP to generate muscle contraction, and also transport cargo around the cell as part of the cytoskeleton. Other ATPases in the cell membrane are ion pumps involved in active transport.
No. Zooplankton feed on phytoplankton. Phytoplankton cannot photosynthesize in the dark. (The Benthric Zone is the lowest level of the ocean/a body of water, no sunlight can really reach there.)
ATP<span> is responsible for cocking (pulling back) the myosin head, ready for another cycle. When it binds to the myosin head, it causes the cross bridge between actin and myosin to detach. </span>ATP<span> then provides the energy to pull the myosin back.</span>