All cells arise from other cells

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    Created by
    Niamh Mumby

    Cards (12)

    • What is the importance of mitosis?
      -Growth of organisms
      -Repair of damaged tissues
      -Asexual reproduction
      -Cloning
    • What are the 6 stages of mitosis?
      Interphase
      Prophase
      Metaphase
      Anaphase
      Telophase
      Cytokinesis
    • Describe what happens at interphase
      The DNA and organelles replicate
    • Describe what happens at prophase
      The chromosomes shorten, thicken and condense
      The cell membrane dissolves
      The chromosomes become visible
    • Describe what happens at metaphase
      The chromosomes line up on the cell equator
      The centrioles produce spindle fibres
    • Describe what happens at anaphase
      The chromatids separate and are pulled to opposite poles of the cell
    • Describe what happens at telophase
      The cell membranes reform
    • Describe what happens at cytokinesis
      Cytoplasm and cell membrane divide into two
      Two daughter cells are formed
    • How is a tumour formed from proto-oncogenes
      They code for proteins that initiate and speed up cell division
      A mutation may cause the protein to increase its function so it becomes an oncogene
      The cell divides at a rapid and uncontrolled rate so a tumour forms
    • How is a tumour formed from tumour suppressor genes?
      They code for proteins that inhibit and slow down cell division
      A mutation may cause the protein to decrease in function
      The cell divides at a rapid and uncontrolled rate so a tumour forms
    • Compare benign and malignant tumours
      -Benign contains non cancerous cells where as malignant contain cancerous cells that divide rapidly and uncontrollably
      -In benign, cells remain localised but in malignant, cells break off to another tissue where secondary tumours can form, called metastasis
      -Benign contain differentiated cells but malignant contain some undifferentiated cells
      -Both can cause blockages and impair normal function
    • Describe binary fission
      -Circular DNA replicated to produce two copies
      -Plasmids replicate to produce a variable number of copies
      -The bacterial cell elongates
      -The cytoplasm divides to produce two daughter cells, each with a single copy of circular DNA