As a human grows, cell numbers increase as a result of mitosis, followed by enlargement of the newly formed cells and of the body.
The diverse parts of our bodies—the many specialized cells that form tissues, organs, and organ systems—originated from just one cell.
These life phases include a prenatal period, which begins with the fertilization of an egg cell and ends at birth, and a postnatal period, which begins at birth and ends with death.
MicroLesson: One Minute Video Lecture - Coming Soon