neurons are specialized cells that generate and conduct electrical impulses throughout the body.
<span>Random fertilization adds to the genetic variation thanks to B)Fusion of sperm and ovum, each having a unique combination of chromosomes, introduces further variation. Fertilization is a process of fusion of sperm and ovum. In a random fertilization, it is expected that sperm and ovum each have a unique combination of chromosomes. Thus, the created zygote will have a unique combination of chromosomes which introduces variation.</span>
Explanation:
Water is the most abundant substance in the body. An average healthy adult is 45 to 75 percent water. Percent of water declines with age. Males have more body water than females.