1 / 17

The Cell Cycle

The Cell Cycle. Why do cells divide?. Growth Repair – broken bones, cuts, regeneration Reproduction Asexual – offspring produced only by one parent Sexual – offspring that have a combination of genetic material from two parents. Scar Story. The cell cycle.

ciqala
Download Presentation

The Cell Cycle

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Cell Cycle

  2. Why do cells divide? • Growth • Repair – broken bones, cuts, regeneration • Reproduction • Asexual – offspring produced only by one parent • Sexual – offspring that have a combination of genetic material from two parents

  3. Scar Story

  4. The cell cycle • Defined: The sequence of growth and division of a cell • Includes interphase, mitosis and cytokinesis

  5. Interphase • Carries on metabolism • Longest part of the cell cycle • 3 parts • 1) G1 (Gap 1 – 1st stage) – cell growth and protein production • 2) S stage (Synthesis – 2nd stage) – Chromosomes are replicated • 3) G2 (gap 2 – 3rd stage) – New organelles and other material are manufactured

  6. Mitosis • Process of nuclear division • Division of cytoplasm • Chromosomes are distributed to daughter cells

  7. Prophase (phase 1) • Longest phase of mitosis • Stringy chromatin coils up into visible chromosomes • Chromosome is in two halves called sister chromatids • Sister chromatids held together by centromere • Nucleus disappears • Nuclear envelope and nucleolus disintegrate

  8. Prophase con’t. • Centrioles migrate to opposite ends of the cell • Only in animal cells • Spindle fibers form between the centrioles • Football shaped, cage-like structure • Made of microtubules

  9. Metaphase (phase 2) • Doubled chromosomes become attached to the spindle • Chromosomes line up on the equator of the cell • One sister chromatid extends to each pole of the cell • Ensures each new cell gets identical and complete chromosomes

  10. metaphase

  11. Anaphase (phase 3) • Centromeres split apart • Chromatoid pairs from each chromosome separate from each other

  12. Telophase (phase 4) • Changes that occurred in prophase are reversed • Chromosomes unwind • Spindle breaks down • Nucleus reappears • Plasma membrane separates the 2 nuclei

  13. telophase

  14. Cytokinesis (cytoplasm division) • Animal cells • Plasma membrane pinches in along the equator • Plant cells • A cell plate forms across the equator

More Related