The contractile vacuole expels excess fluid from the cell.
When a cell is not dividing, the DNA is loosely spread throughout the nucleus in a threadlike form called chromatin.
<span>In the "all or none" law of muscle contraction, it states that when the stimulus applied exceeds threshold then the the nerve sending signals to a few muscle fibers will give a complete response; contraction. Graded response is dependent on how many motor units have been recruited. The more motor units, the greater the force in the contraction.</span>
The bear affects the ecosystem by eating plants and animals which lowers invasive species levels.
Answer:
as the field of science, biology help as to understand the living world and the ways it's many species
