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cells : principles and applications of science 

  • cell membrane - controls what moves in and out of the cell

  • mitochondria - where aerobic respiration takes place

  • cytoplasm - where most of the chemical reactions take place

  • nucleus - contains genetic information

  • nuclear membrane - movement of particles in and out of the cell

  • starch grains - stores starch

Microscopes : history

  • first names in 1609

  • first cells observed in 1665 which were cork plant cells (dead)

  • first living cells observed around 1674 - 1683 (living cells)

  • nucleus first observed in 1831

  • universal cell theory 1839

  • evidence for new cells generated from existing cells in 1892

how compound light microscopes work

  • it has two lens,objective and eyepiece

  • the objective lens is placed closed to the specimen

  • the eyepiece is the lens through which specimen is viewed

  • both lens magnify the same

  • calculations

    eye piece = x10 or x20

    objective lens = x4,x10,x40,x100

    [formula = eye piece x objective]

  • a transition light microscope forms an image from the light passing through the specimen

  • specimen must be thin

  • magnification

  • %%[magnification = measured size of the image / actual size of the object]%%⭐

Characters of living things

  • growth

  • reproduction

  • releases energy

  • nutrition

  • excretion

  • sensitivity

  • movement

  • made up of cells

principles of living organisms

  • cells and tissues

  • types of tissues

  • structures found within cells

  • function of structures found within cells

  • difference between type of cell

MT

cells : principles and applications of science 

  • cell membrane - controls what moves in and out of the cell

  • mitochondria - where aerobic respiration takes place

  • cytoplasm - where most of the chemical reactions take place

  • nucleus - contains genetic information

  • nuclear membrane - movement of particles in and out of the cell

  • starch grains - stores starch

Microscopes : history

  • first names in 1609

  • first cells observed in 1665 which were cork plant cells (dead)

  • first living cells observed around 1674 - 1683 (living cells)

  • nucleus first observed in 1831

  • universal cell theory 1839

  • evidence for new cells generated from existing cells in 1892

how compound light microscopes work

  • it has two lens,objective and eyepiece

  • the objective lens is placed closed to the specimen

  • the eyepiece is the lens through which specimen is viewed

  • both lens magnify the same

  • calculations

    eye piece = x10 or x20

    objective lens = x4,x10,x40,x100

    [formula = eye piece x objective]

  • a transition light microscope forms an image from the light passing through the specimen

  • specimen must be thin

  • magnification

  • %%[magnification = measured size of the image / actual size of the object]%%⭐

Characters of living things

  • growth

  • reproduction

  • releases energy

  • nutrition

  • excretion

  • sensitivity

  • movement

  • made up of cells

principles of living organisms

  • cells and tissues

  • types of tissues

  • structures found within cells

  • function of structures found within cells

  • difference between type of cell

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