The larger a cell becomes: 1) the more demands the cell places on its. 2) the more trouble the cell has moving enough and across the cell membrane.

Transcription

1 10 1 Cell Growth Why are cells small? The larger a cell becomes: 1) the more demands the cell places on its. 2) the more trouble the cell has moving enough and across the cell membrane. The rate at which food, oxygen, water, and wastes are moved in and out of the cell is dependent on the of the cell. The rate at which food, oxygen and water are used and waste is produced depends on the cell s.

2 10 1 Cell Growth Limits to Cell Growth As the size of a cell increases, its increases faster than the surface area. The in the cell s of surface area to volume makes it more difficult for the cell to needed materials in and waste products out quickly enough for the cell to survive.

3 10 1 Cell Growth Division of the Cell Parent Cell Before it becomes too large ( SA/V), a growing cell divides forming two cells. The process by which a cell divides into two new daughter cells is called and has two parts: 1) 2)

4 The Cell Cycle The cell cycle is the series of events that cells go through as they and. is the period of growth that occurs between. During the cell cycle: 1) a cell 2) for division 3) to form two cells, each of which begins the again

5 Cell Division Events of the Cell Cycle Animation

6 Chromosomes information is passed from one generation to the next on. Before cell division, each chromosome is, or copied. Each chromosome consists of two identical sister. Each pair of chromatids is attached at an area called the. When the cell divides, the chromatids. Each new cell gets one chromatid (unduplicated chromosome)

7 Animation

8 Mitosis In eukaryotes, cell division occurs in two major stages. The first stage, division of the cell, is called. The second stage, division of the cell cytoplasm, is called.

9 Prophase is the first and longest phase of mitosis. The separate and take up positions on opposite sides of the nucleus. The centrioles lie in a region called the. The centrosome helps to organize the, a fanlike microtubule structure that helps separate the chromosomes. condenses into chromosomes and the nuclear breaks down.

10 Metaphase The second phase of mitosis is. The chromosomes line up across the of the cell. connect the of each chromosome to the of the spindle.

11 Anaphase is the third phase of mitosis. The sister chromatids into individual. The chromosomes continue to move until they have separated into two groups.

12 is the fourth and final phase of mitosis. Chromosomes gather at opposite ends of the cell and uncoil into. Nuclear envelopes reform around the nuclei. Telophase

13 Cytokinesis During, the and pinch in half. Each cell has an set of duplicate chromosomes. Animation

14 Cytokinesis in Plants In, a structure known as the cell forms midway between the divided nuclei. The cell plate gradually develops into a separating. A cell then begins to appear in the cell plate.

15 10-3 Regulating the Cell Cycle Controls on Cell Division Experiments show that normal cells will until they come into with other cells. Then they respond by not. This demonstrates that controls on cell growth and division can be turned and.

16 10-3 Regulating the Cell Cycle A sample of cytoplasm is removed from a cell in mitosis. Cell Cycle Regulators The sample is injected into a second cell in G2 of interphase. As result, the second cell enters mitosis. The cell cycle is regulated by a specific. The amount of this protein in the cell and falls in with the cell cycle. Scientists call this protein because it seemes to regulate the cell cycle. Cyclin regulates the of the cell cycle in eukaryotic cells.

17 10-3 Regulating the Cell Cycle Cell Cycle Regulators Cell cycle regulatory proteins that respond to events inside the cell are called regulators. Internal regulators allow the cell cycle to only when certain processes have happened inside the cell. Regulatory proteins that respond to events outside the cell are called regulators. External regulators direct cells to up or slow down the cell cycle.

18 10-3 Regulating the Cell Cycle Uncontrolled Cell Growth Animation is a disorder in which some of the body's own cells lose the ability to control and do not respond to that regulate the growth of most cells. Cancer cells uncontrollably and form masses of cells called that can damage the surrounding tissues ( ). Cancer cells may break loose from tumors and throughout the body ( ), disrupting normal activities and causing serious medical problems or even death.