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The Cell Cycle. Division of the Cell : All cells come from preexisting cells. . Why do cells divide?. Growth and Development Repair (Healing) Reproduction ( We will talk about this later). Division of the Cell : All cells come from preexisting cells. . Why do cells divide?.
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Division of the Cell : All cells come from preexisting cells. Why do cells divide? • Growth and Development • Repair (Healing) • Reproduction • ( We will talk about this later)
Division of the Cell : All cells come from preexisting cells. Why do cells divide? Growth and Development Humans start off as one single cell, and by the time they are adults, they have over 10 trillion cells!!! This increase in the number of cells also allows for some of those cells to be specialized for various functions. This is important to the survival of many organisms. A RESULT OF MITOSIS
Division of the Cell : All cells come from preexisting cells. Why do cells divide? Repair (Healing) Some organism, are able to regenerate lost limbs (such as arms or tails). Humans can repair skin, blood vessels and bones, or replace cells that have died. You have a “new” skin every 28 days! A RESULT OF MITOSIS
Division of the Cell : All cells come from preexisting cells. How do cells divide? PROKARYOTES EUKARYOTES Have a nucleus containing many chromosomes Divide by Mitosis • Have only one circular chromosome • Divide by binary fission VS.
Division of the Cell : All cells come from preexisting cells. How do cells divide? PROKARYOTES EUKARYOTES Binary fission in E. Coli Mitosis in White Fish VS.
The Cell Cycle: Eukaryotes The series of events that cells go through as they grow and divide. During the cell cycle, a cell grows, prepares for division, and divides to form two identical daughter cells, each of which then begins the cycle again.
Interphase: The longest phase of the cell cycle Has Three Stages • G1 Phase: • Period of cell growth • New proteins & organelles • S Phase: • Chromosomes are replicated • DNA synthesis • G2: The Shortest of the 3 phases • organelles and molecules required for cell division are produced
M Phase: Mitosis and Cytokinesis Mitosis consists of 4 stages • Prophase • Metaphase • Anaphase • Telophase Cytokinesis The division of the cytoplasm, occurs at the same time as telophase.