Presentation is loading. Please wait.

Presentation is loading. Please wait.

Cell Division Mitosis Chapter 10. Why do cells divide, rather than continually grow forever? The larger a cell becomes, the more demands the cell places.

Similar presentations


Presentation on theme: "Cell Division Mitosis Chapter 10. Why do cells divide, rather than continually grow forever? The larger a cell becomes, the more demands the cell places."— Presentation transcript:

1 Cell Division Mitosis Chapter 10

2 Why do cells divide, rather than continually grow forever? The larger a cell becomes, the more demands the cell places of its DNA. The cell also has more trouble moving enough nutrients and wastes across the cell membrane.

3 Division of the Cell Before it becomes too large, a growing cell divides forming two daughter cells. The process by which a cell divides into new daughter cells is called cell division. Before cell division occurs, the cell replicates, or copies, all of its DNA. Thus, each daughter cell gets one complete set of genetic information.

4 Cell Division Cell division is complex and occurs in 2 main stages: –Mitosis-division of cell nucleus –Cytokinesis-division of cytoplasm Genetic information is carried by chromosomes. –Before cell division each chromosome is replicated, or copied forming two identical sister chromatids, which will be separated from each other when the cell divides.

5 The Cell Cycle The cell cycle is a series of events that cells go through as they grow and divide. During the cell cycle, the following happens: Cell grows (interphase) Cell prepares for division (interphase) Cell divides to form 2 daughter cells (each of which further divide) (cell division)

6 Events of the Cell Cycle Interphase –G 1 phase Cell grows (increases in size and makes new proteins and organelles) –S phase Replication of chromosomes/DNA synthesized –G 2 phase Organelles and molecules needed for cell division produced.

7 Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming Section 10-2 Figure 10–5 Mitosis and Cytokinesis

8 Mitosis (M phase) When the events of the G2 phase are completed, the cell is ready to enter the M phase and begin cell division. The events of mitosis are divided into four phases: –Prophase –Metaphase –Anaphase –Telophase

9 Prophase 1 st phase of mitosis where: –Centrioles take their place at opposite sides of the cell –Spindle fibers form –Chromatin coils to form chromosomes –Nuclear envelope breaks down

10 Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming Section 10-2 Figure 10–5 Mitosis and Cytokinesis

11 Metaphase The chromosomes line up across the center of the cell Each chromosome is connected to a spindle fiber at its centromere.

12 Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming Section 10-2 Figure 10–5 Mitosis and Cytokinesis

13 Anaphase Sister chromatids separate into individual chromosomes and are moved apart

14 Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming Section 10-2 Figure 10–5 Mitosis and Cytokinesis

15 Telophase The chromosomes gather at opposite ends of the cell and lose their distinct shapes. Two new nuclear envelopes will form.

16 Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming Section 10-2 Figure 10–5 Mitosis and Cytokinesis

17 Cytokinesis The cytoplasm pinches in half. Each daughter cell has an identical set of duplicate chromosomes.

18 How will I ever remember the phases? P M A T

19 This is how you can remember the phases: Please Make Another Touchdown


Download ppt "Cell Division Mitosis Chapter 10. Why do cells divide, rather than continually grow forever? The larger a cell becomes, the more demands the cell places."

Similar presentations


Ads by Google