Complete the following paragraph by adding the correct terms.

Cells can make new cells. One cell can (a) ____________ into two new cells. This is called (b)__________________. The process of cell division goes through various states. First, the cell nucleus (c)________________ into two. A new cell surface membrane then (d)____________ the cell divides. The two new cells are called (e)_______________ and they are small. They will grow and become larger. They grow by getting (f)______________ from the food that is eaten. Once they grow to full size they can also (g)_____________. If cells divide more quickly than they should, or divide in the wrong way, (h)_____________ can develop.

5. Why is RNA necessary to act as a messenger? Why can't the code be taken directly from the DNA? How do some cells become brain cells and others become skin cells, when the DNA in ALL the cells is exactly the same? In other words, if the instructions are exactly the same, how does one cell become a brain cell and another a skin cell?