68 Mitosis and the Cell Cycle Key idea Mtosis an important part of the cel e in which the replicated chromosomes is are separated and the cell divides, two new cels. Mitosis is a stage in the cell cycle An overview of mitosis The life cycle of a cell is called the cell cycle. It is divided into a number of stages in which specific activities occur. Mtosis is one stags ot the cet cyclo. The activities carried out during the cell eyde include growth of the call, teplicason of the DNA, condensation of the chromosomes, minosis, and onokinesis M-phase (mitosis and cyylokinesis)is part of the cell cycle in which the parent cel divdes in two to produce two genetically identical daughter cells (right). Mnosis is one of the shortest stages of the cell cycle. When cell is not undergoing mitosis, It is said to be in interphase. Interphase accounts for 90% of the oel eyde. The Del divides toming identca daughter The ohromosome Number At any one time, only smal proporton of te oels in undergoing misosis. The majony of the cells will be in interphase. The cell cycle Second gap phase: s Phase: Chromosome Cells spend most of their time in interphase interphase is devided into thrae stages fright: The fist gap phase. During interphase the oel grows, camies out The cell cycle its normal activities, and replicates its DNA in preparation for cel dvison interphase is not a stage in mitosis. Mitosis and cytokinesis (M-phase) Mtosis and cytokinesis ooour during Mphase. During mitosis, the cell nucleus (containing the replicated DNA) divides in two equa parts. First gap phase: Cytokinesis occurs at the end of M-phase. the two tells saparate. Coll growth and During cytokinesis the cel cytoplasm divides, from nudaar division. and two new daughter are produced. Solution Answer 1. The purpose of mitosis is cell division and maintaining the ploidy levels of the organism. Answer 2. The cell grows before mitosis and the chromosomes of the cells double before the mitosis takes place in a cell. Answer 3. During Interphase, the cell grows in size, maintain its functions and the chromosome doubles. During Mitosis: (i) Prophase and prometaphase: The DNA condenses to form Chromosomes, Nuclear membrane dissolves, The polar bodies migrates to the opposite ends of the cell. Spindle fibers begin to form. (ii) Metaphase: Chromosomes align in the middle of cells and centromeres are attached to the spindle fibers. (iii) Anaphase: Centromeres of the chromosomes break and sister chromatids move towards opposite poles. (iv) Nuclear membrane forms and Cytokinesis begins During Cytokinesis: The cell divides into two cells..

1. 68 Mitosis and the Cell Cycle Key idea Mtosis an important part of the cel e in which the
replicated chromosomes is are separated and the cell divides, two new cels. Mitosis is a stage in
the cell cycle An overview of mitosis The life cycle of a cell is called the cell cycle. It is divided
into a number of stages in which specific activities occur. Mtosis is one stags ot the cet cyclo.
The activities carried out during the cell eyde include growth of the call, teplicason of the DNA,
condensation of the chromosomes, minosis, and onokinesis M-phase (mitosis and cyylokinesis)is
part of the cell cycle in which the parent cel divdes in two to produce two genetically identical
daughter cells (right). Mnosis is one of the shortest stages of the cell cycle. When cell is not
undergoing mitosis, It is said to be in interphase. Interphase accounts for 90% of the oel eyde.
The Del divides toming identca daughter The ohromosome Number At any one time, only smal
proporton of te oels in undergoing misosis. The majony of the cells will be in interphase. The
cell cycle Second gap phase: s Phase: Chromosome Cells spend most of their time in interphase
interphase is devided into thrae stages fright: The fist gap phase. During interphase the oel
grows, camies out The cell cycle its normal activities, and replicates its DNA in preparation for
cel dvison interphase is not a stage in mitosis. Mitosis and cytokinesis (M-phase) Mtosis and
cytokinesis ooour during Mphase. During mitosis, the cell nucleus (containing the replicated
DNA) divides in two equa parts. First gap phase: Cytokinesis occurs at the end of M-phase. the
two tells saparate. Coll growth and During cytokinesis the cel cytoplasm divides, from nudaar
division. and two new daughter are produced.
Solution
Answer 1. The purpose of mitosis is cell division and maintaining the ploidy levels of the
organism.
Answer 2. The cell grows before mitosis and the chromosomes of the cells double before the
mitosis takes place in a cell.
Answer 3.
During Interphase, the cell grows in size, maintain its functions and the chromosome doubles.
During Mitosis:
(i) Prophase and prometaphase: The DNA condenses to form Chromosomes, Nuclear membrane
dissolves, The polar bodies migrates to the opposite ends of the cell. Spindle fibers begin to
form.
(ii) Metaphase: Chromosomes align in the middle of cells and centromeres are attached to the
spindle fibers.
(iii) Anaphase: Centromeres of the chromosomes break and sister chromatids move towards
opposite poles.

2. (iv) Nuclear membrane forms and Cytokinesis begins
During Cytokinesis: The cell divides into two cells.