Cell division is required for the growth and development of all multicellular organisms. Generally speaking, cell division equals growth. At the beginning of your life, cell division transformed you from a fertilized egg into a baby, and more recently, from a baby into an AP Bio student.

Cell division is best described as a cycle. A cell spends most of its time in interphase, when it grows and prepares to divide by copying of all of its contents - including its DNA. The actual division of the cell occurs during mitosis, or “M” phase, which results in two identical daughter cells that start duplicating their contents in preparation for their own division - and the cycle begins again! The cell cycle is a biological process.

Throughout this presentation, we will keep track of where we are in the cycle with this cell cycle process icon. Growth from a baby into an adult takes about 18 years and occurs in spurts, so cell division must speed up and slow down. At some point, our bodies stop growing, so our cells must stop dividing altogether.

How is this controlled? Several things tell cells whether to rest or to continue around the cycle. For example, a chemical signal called human growth hormone, or HGH, triggers growth in children by telling cells throughout the body to divide. Children that don’t produce enough Human Growth Hormone have a condition called Growth Hormone Deficiency, or GHD, and are short. Regulation of the cell cycle is essential for proper growth and for keeping your body size in check.

we're going to investigate the phases of the cell cycle. Then we’ll focus on the mitosis phase of the cell cycle, and discover how a structure called the mitotic spindle coordinates proper nuclear division. Finally, we’ll observe mitosis in both plants and animals in an experiment.

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