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The Cell Cycle 5A. How eukaryotic cells divide to make new cells. Just like people have phases of development,. Cells have phases too. In somatic (body) cells, a parent cell produces 2 daughter cells. The purpose of mitosis is for growth and repair of tissue. Three Phases or Stages.
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The Cell Cycle5A How eukaryotic cells divide to make new cells
In somatic (body) cells, a parent cell produces 2 daughter cells.The purpose of mitosis is for growth and repair of tissue.
Three Phases or Stages Interphase M (Mitosis) phase Cytokinesis
Interphase • DNA and organelles replicate • Cell spends most of its life in this stage
Stages of Interphase G1 (growth) S (synthesis) G2 (growth)
G1 (growth) • Aka First Gap • The cell grow larger • Makes proteins and organelles
S (synthesis) • DNA replication occurs - genetic material is duplicated so each daughter cell contains the same amount of genetic material as the parent cell • Chromosomes duplicate to form sister chromatids
G2 (growth) • Aka Second Gap • More growth & protein synthesis occurs • preparing for cell division
M phase • Aka Mitosis • Shortest of all phases • Division of the nucleus
Mitosis • Nucleus divides • Duplicated DNA is divided into two new nuclei
Stages of Mitosis Prophase Metaphase Anaphase Telophase
Prophase • Nuclear membrane breaks down • Genetic material (chromosomes) enlarges, thickens &condenses • In the cytoplasm, Centrioles migrate to opposite ends of poles • Microtubules attach to centrioles
Metaphase • Duplicated chromosomes line up on the equator of the cell • Spindles attach to chromosomes at the centromere & pull the sister chromatids into a line in the center of the cell
Anaphase • Shortest phase • As the spindle contracts, the sister chromatids separate and are pulled to opposite sides of the cell
Telophase • New nuclear membranes form to separate the genetic material • Chromosomes shrink • Spindle breaks apart
Cytokinesis • Occurs AFTER telophase and BEFORE interphase • Cytoplasm divides • Forms 2 new cells
What happens when cells divide at an uncontrollable rate? CANCER 5D