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