Presentation is loading. Please wait.

Presentation is loading. Please wait.

Copyright Pearson Prentice Hall

Similar presentations


Presentation on theme: "Copyright Pearson Prentice Hall"— Presentation transcript:

1 Copyright Pearson Prentice Hall
Prentice Hall Biology Copyright Pearson Prentice Hall

2 Copyright Pearson Prentice Hall
10-2 Cell Division Photo Credit: © CAMR/A.B. Dowsett/Science Photo Library/Photo Researchers, Inc. Copyright Pearson Prentice Hall

3 Copyright Pearson Prentice Hall
The Cell Cycle During the cell cycle: a cell grows prepares for division divides to form two daughter cells, each of which begins the cycle again Copyright Pearson Prentice Hall

4 Copyright Pearson Prentice Hall
The Cell Cycle Cell Cycle The cell cycle is the series of events that cells go through as they grow and divide. Interphase is the period of growth that occurs between cell divisions. Copyright Pearson Prentice Hall

5 Copyright Pearson Prentice Hall
The Cell Cycle The cell cycle consists of four phases: G1 (First Gap Phase) S Phase G2 (Second Gap Phase) M Phase G0 Phase (Resting phase) Copyright Pearson Prentice Hall

6 Events of the Cell Cycle
During G1, the cell increases in size synthesizes new proteins and organelles Copyright Pearson Prentice Hall

7 Events of the Cell Cycle
During the S phase, chromosomes are replicated DNA synthesis takes place Once a cell enters the S phase, it usually completes the rest of the cell cycle. Copyright Pearson Prentice Hall

8 Copyright Pearson Prentice Hall
Cell Division DNA to Chromatin to Chromosomes Copyright Pearson Prentice Hall

9 Copyright Pearson Prentice Hall
Chromatin: consists of DNA tightly coiled around proteins called histones Copyright Pearson Prentice Hall

10 Chromosomes Chromosomes Genetic information is passed from one generation to the next on chromosomes. Before cell division, each chromosome is duplicated, or copied.

11 Copyright Pearson Prentice Hall
Chromosomes Each chromosome consists of two identical “sister” chromatids. Each pair of chromatids is attached at an area called the centromere. Sister chromatids Photo Credit: © Gunther F. Bahr/AFIP/Stone Centromere Copyright Pearson Prentice Hall

12 Copyright Pearson Prentice Hall
Chromosomes DNA Copyright Pearson Prentice Hall

13 Events of the Cell Cycle
The G2 Phase (Second Gap Phase) Preparing for Cell Division organelles and molecules required for cell division are produced Once G2 is complete, the cell is ready to start the M phase—Mitosis Copyright Pearson Prentice Hall

14 Events of the Cell Cycle
During the cell cycle, the cell grows, replicates its DNA, and divides into two daughter cells. DNA synthesis takes place during the S phase. Cell division takes place during the M phase. G1 and G2 are gap phases. Copyright Pearson Prentice Hall

15 Copyright Pearson Prentice Hall
Cell Division In eukaryotes, cell division occurs in two major stages. The first stage, division of the cell nucleus, is called mitosis. The second stage, division of the cell cytoplasm, is called cytokinesis. Copyright Pearson Prentice Hall

16 Copyright Pearson Prentice Hall
Chromosomes When the cell divides, the chromatids separate. Each new cell gets one chromatid. Copyright Pearson Prentice Hall

17 Copyright Pearson Prentice Hall
Mitosis Mitosis Biologists divide the events of mitosis into four phases: (PMAT) Prophase Metaphase Anaphase Telophase Copyright Pearson Prentice Hall

18 Copyright Pearson Prentice Hall
Mitosis Most eukaryotic cells go through a regular cycle of interphase, mitosis and cytokinesis. Mitosis has four phases: Prophase, Metaphase, Anaphase and Telophase. The events shown here are typical of animal cells. Mitosis Copyright Pearson Prentice Hall

19 Chromosomes (paired chromatids)
Mitosis Section 10-2 Spindle forming Prophase Prophase Chromosomes (paired chromatids) Centromere Most eukaryotic cells go through a regular cycle of interphase, mitosis and cytokinesis. Mitosis has four phases: Prophase, Metaphase, Anaphase and Telophase. The events shown here are typical of animal cells. Click to Continue Copyright Pearson Prentice Hall

20 Copyright Pearson Prentice Hall
Mitosis Spindle forming Prophase Prophase is the first and longest phase of mitosis. The centrioles separate and take up positions on opposite sides of the nucleus. Centromere Chromosomes (paired chromatids) Copyright Pearson Prentice Hall

21 Copyright Pearson Prentice Hall
Mitosis Spindle forming The spindle is forming and the pairs chromosomes are visible. The centrosome helps to organize the spindle, a fanlike microtubule structure that helps separate the chromosomes. Centromere Chromosomes (paired chromatids) Copyright Pearson Prentice Hall

22 Copyright Pearson Prentice Hall
Mitosis Spindle forming Chromatin condenses into chromosomes. The centrioles separate and a spindle begins to form. The nuclear envelope breaks down. Centromere Chromosomes (paired chromatids) Copyright Pearson Prentice Hall

23 Copyright Pearson Prentice Hall
Mitosis Metaphase Centriole Spindle Centriole Metaphase Click to Continue Copyright Pearson Prentice Hall

24 Copyright Pearson Prentice Hall
Mitosis Centriole Metaphase The second phase of mitosis is metaphase. The chromosomes line up across the center of the cell. Microtubules connect the centromere of each chromosome to the poles of the spindle. Spindle Copyright Pearson Prentice Hall

25 Individual chromosomes
Mitosis Anaphase Individual chromosomes Anaphase Copyright Pearson Prentice Hall

26 Copyright Pearson Prentice Hall
Mitosis Anaphase Anaphase is the third phase of mitosis. The sister chromatids separate into individual chromosomes. The chromosomes continue to move until they have separated into two groups. Individual chromosomes Copyright Pearson Prentice Hall

27 Nuclear envelope reforming
Mitosis Telophase Nuclear envelope reforming Telophase Copyright Pearson Prentice Hall

28 Copyright Pearson Prentice Hall
Mitosis Telophase Telophase is the fourth and final phase of mitosis. Chromosomes gather at opposite ends of the cell and lose their distinct shape. Copyright Pearson Prentice Hall

29 Copyright Pearson Prentice Hall
Mitosis A new nuclear envelope forms around each cluster of chromosomes. Copyright Pearson Prentice Hall

30 Copyright Pearson Prentice Hall
Cytokinesis Cytokinesis Cytokinesis Copyright Pearson Prentice Hall

31 Copyright Pearson Prentice Hall
Cytokinesis During cytokinesis, the cytoplasm pinches in half. Each daughter cell has an identical set of duplicate chromosomes Copyright Pearson Prentice Hall

32 Copyright Pearson Prentice Hall
Cytokinesis in Plants In plants, a structure known as the cell plate forms midway between the divided nuclei. Cell plate Cell wall Copyright Pearson Prentice Hall

33 Copyright Pearson Prentice Hall
The G0 Phase (resting phase) The cell leaves the cell cycle and quits dividing. This may be a temporary resting period or more permanent. Ex: Nerve cells and heart muscle cells no longer divide after reaching maturity. Copyright Pearson Prentice Hall

34 Copyright Pearson Prentice Hall
10-2 - or - (must have QuickTake software installed on the computer you are using for this presentation) Copyright Pearson Prentice Hall

35 Copyright Pearson Prentice Hall
10-2 The series of events that cells go through as they grow and divide is called the cell cycle. mitosis. interphase. cytokinesis. Copyright Pearson Prentice Hall

36 Copyright Pearson Prentice Hall
10-2 The phase of mitosis during which the chromosomes line up across the center of the cell is prophase. metaphase. anaphase. telophase. Copyright Pearson Prentice Hall

37 Copyright Pearson Prentice Hall
10-2 Cytokinesis usually occurs at the same time as telophase. after telophase. during interphase. during anaphase Copyright Pearson Prentice Hall

38 Copyright Pearson Prentice Hall
10-2 DNA replication takes place during the S phase of the cell cycle. G1 phase of the cell cycle. G2 phase of the cell cycle. M phase of the cell cycle. Copyright Pearson Prentice Hall

39 Copyright Pearson Prentice Hall
10-2 During mitosis, “sister” chromatids separate from one another during telophase. interphase. anaphase. metaphase. Copyright Pearson Prentice Hall

40 END OF SECTION


Download ppt "Copyright Pearson Prentice Hall"

Similar presentations


Ads by Google