Growth and development at the cellular level. Cell division, growth, & differentiation

Seeing that all organisms are comprised of cells (type into your browser:  photomicrographs animal tissue/ also, photomicrographs plant tissues) pose the question: How does the organism grow? Let’s examine a rapidly a growing tissue such as a root tip (type into your browser: mitosis onion root tip photomicrographs/) In most cells, a large nut-like body (the nucleus) is seen. In some cells, worm-like bodies (chromosomes) are seen. After countless hours of observation, scientists pieced together what was going on–A process of cell division which they called mitosis. Modern equipment and techniques enable it to now be seen in real life: See this video:

The flowing animation of mitosis may be helpful in sorting out the process.

Conclusion: All cells come from a preexisting cell via the process of cell division (mitosis). Just as important as cell division–after their formation the new cells go on to grow and then differentiate (become different) to take on the shape an functions of appropriate to the organ in which they are located. Thus, the growth and development of every organism is underlain by cell division, growth, and differentiation.  See further in the text. Please post questions.