IntroductionIntroductionThe cell cycle is necessary for all multi-cellular The cell cycle is necessary for all multi-cellular

organisms. There are different parts, organisms. There are different parts, including interphase, mitosis, and including interphase, mitosis, and cytokinesis. Mitosis consists of prophase, cytokinesis. Mitosis consists of prophase, metaphase, anaphase, and telophase. At metaphase, anaphase, and telophase. At first, the cell grows and develops. The first, the cell grows and develops. The chromosomes, towards the end of chromosomes, towards the end of interphase, become visible. They line up interphase, become visible. They line up along the center of the cell and are attached along the center of the cell and are attached to spindle fibers. The chromosomes split and to spindle fibers. The chromosomes split and are pulled to opposite sides of the cell. They are pulled to opposite sides of the cell. They began to cluster and make two new cells. In began to cluster and make two new cells. In cytokinesis, two daughter cells form.cytokinesis, two daughter cells form.

What you need to What you need to knowknow

What chromosomes areWhat chromosomes areA structure made of DNA and protein in the A structure made of DNA and protein in the nucleus of a eukaryotic cellnucleus of a eukaryotic cell

What mitosis isWhat mitosis isThe process of cell division where the nucleus The process of cell division where the nucleus divides into two nucleidivides into two nuclei

What cell division isWhat cell division isThe process of one cell dividing into two The process of one cell dividing into two daughter cellsdaughter cells

http://www.ba-education.com/dna/mitosis.jpg

A picture of all the phases...

InterphaseInterphaseThe cell grows and develops.The cell grows and develops.

Towards the end of this phase, the DNA Towards the end of this phase, the DNA (with the chromosomes) double.(with the chromosomes) double.

Longest part of cell cycleLongest part of cell cycle

ProphaseProphaseThe chromosomes are visible.The chromosomes are visible.

The nuclear membrane disappears.The nuclear membrane disappears.

Nucleolus vanishes.Nucleolus vanishes.

MetaphaseMetaphaseThe chromosomes line up across the The chromosomes line up across the center.center.

Spindle fibers attach to the center of Spindle fibers attach to the center of the chromosome.the chromosome.

AnaphaseAnaphaseChromosomes split away from each Chromosomes split away from each other.other.

Each half is pulled to opposite sides of Each half is pulled to opposite sides of the cell.the cell.

Cell is splitting a bit.Cell is splitting a bit.

TelophaseTelophaseChromosomes cluster in the center of Chromosomes cluster in the center of each new cell.each new cell.

Nuclear membrane begins to form.Nuclear membrane begins to form.

Cells began separating.Cells began separating.

CytokinesisCytokinesisCytoplasm divides.Cytoplasm divides.

Two daughter cells form.Two daughter cells form.

It has the same number of It has the same number of chromosomes as the parent cell.chromosomes as the parent cell.

Each cell starts interphase in the Each cell starts interphase in the endless cycle.endless cycle.

Extra Places for Extra Places for InformationInformation

http://www.dmacc.edu/instructors/http://www.dmacc.edu/instructors/mitosis.htmitosis.ht

http://www.stanford.edu/group/http://www.stanford.edu/group/Urchin/mitosis.htm (animation of Urchin/mitosis.htm (animation of mitosis)mitosis)

http://www.johnkyrk.com/mitosis.htmlhttp://www.johnkyrk.com/mitosis.html

http://www.biologycorner.com/bio1/http://www.biologycorner.com/bio1/cellcycle.htmlcellcycle.html

QuizQuizQ. 1 What happens in prophase?Q. 1 What happens in prophase?

Q. 2 In which phase do the spindle fibers Q. 2 In which phase do the spindle fibers attach to the center of each attach to the center of each chromosome?chromosome?

Q.3 What is the last phase in the cycle? Q.3 What is the last phase in the cycle? (the phase in which the cells completely (the phase in which the cells completely split)split)

Q. 4 What is the longest part of the cell Q. 4 What is the longest part of the cell cycle?cycle?

Quiz AnswersQuiz AnswersA. 1 Chromosomes are visible, the A. 1 Chromosomes are visible, the nuclear membrane and nucleolus nuclear membrane and nucleolus vanish.vanish.

A. 2 MetaphaseA. 2 Metaphase

A. 3 CytokinesisA. 3 Cytokinesis

A. 4 InterphaseA. 4 Interphase

Conclusion (A Conclusion (A brief summary)brief summary)

The cell cycle is the period of time from the The cell cycle is the period of time from the beginning of one cell division to the beginning of one cell division to the next. There are three phases of the cell next. There are three phases of the cell cycle is interphase, mitosis, and cycle is interphase, mitosis, and cytokinesis. Mitosis is divided into four cytokinesis. Mitosis is divided into four phases, prophase, metaphase, phases, prophase, metaphase, anaphase, and telophase. In interphase, anaphase, and telophase. In interphase, the cell grows. In mitosis, the nucleus the cell grows. In mitosis, the nucleus divides. By the end of cytokinesis, two divides. By the end of cytokinesis, two daughter cells form, and interphase daughter cells form, and interphase starts again. starts again.