the Cell Cycle

• longest stage • DNA duplicates and is very long, thin, invisible strands each chromosome is copied to produce 2 sister chromatids attached at the centromere (contains identical genetic info.)

made up of DNA and is found in the nucleus

one of the two identical strands of DNA that make up a chromosome

structure that colds chromatids together as chromosomes

threadlike structure which helps move chromosomes during cell division attaches to the centromere

• pro means “before” • chromosomes condense, thicken and become visible • nuclear membrane begins to disappear • spindle fibers begin to form

• meta means “mid” • longest phase in mitosis • chromosomes line up in the middle of the cell • each chromosome becomes attached to 2 spindle fibers

• ana means “back” • shortest phase in mitosis • centromere splits and sister chromatids separate and are now known as “daughter chromosomes” • daughter chromosomes move to opposite ends of the cell

• telo means “end” • spindle fibers start to disappear • membrane form around 2 new daughter nuclei, one at each end of the cell • chromosomes become thin and invisible

• division of the cytoplasm • provides 2 genetically identical daughter cells • division occurs as the cell membrane is pinched off in the center (animal cell: cleavage furrow, plant cell: cell plate)

a) receives signals from surrounding cells b) not enough nutrients c) DNA has not been replicated d) DNA is damaged

when the DNA is damaged and the cell ignores the checkpoints, which leads to uncontrolled cell growth