The Cell by dfhdhdhdhjr


									The Cell and The Organelles
The Cell
   The structural, functional and biological unit of all organisms.
     The basic unit of life

   Self-replicating unit that can be either exist as
     functional independent unit of life in a unicellular organism
           Example: Bacteria, yeast
       OR
       as sub-unit in a multicellular organism (such as in plants and
           specialized into carrying out particular functions towards the cause of the
            organism as a whole
               Example: Brain cells, blood cells, etc

   A membrane bound structure containing biomolecules, such as
    DNA, proteins, and sugars
The Cellular Membrane

    All cells have a semi-
     permeable membrane
      Barrier between cell and
    Controls the entrance and
     exit of substances
      Protection

    Keeps the inside of the cell
     in “harmony” (balance in
     acidity, temperature, salt
     concentration, etc)
    Supports the cell
The Cell Wall
   The outer layer of a
    plant cell
   Rigid and strong
       Support (grow tall)
       Protection
   Allows water, oxygen
    and carbon dioxide to
    pass into and out of cell
The Cytoplasm
   Clear, thick, jellylike material found inside all
   Supports /protects cell organelles
The Centrioles
   Each is a group of
    fused microtubules
   Make up the
       Internal movement of
       Movement of
        chromosomes during cell
       Contraction of muscle
The Organelles
   The "little organs” of a cell
   They are membrane-bound compartments
   They have specific functions
The Nucleus
   Oval organelle in which DNA can be found
       DNA controls cell activities
   Has a nuclear membrane that controls
    movement of materials in/out of the nucleus
       Protects DNA
The Endoplasmic Reticulum (ER)
   Network of tubes or membranes
   Carries materials through cell
   Can be
       Smooth (no granules on the surface – the
        granules are ribosomes)
       Rough (granules on the surface)
The Ribosomes
   Small bodies free or attached to E.R.
   Their function is to produce proteins
The Mitochondria
   Bean-shaped with inner membranes
   Place where sugar molecules are broken
    down into energy
       Cellular respiration
The Chloroplasts
   Green, oval structures found in plant cells
       Contain the green pigment chlorophyll
   Place where energy from sun is utilized to
    make food for the plant
       Photosynthesis
The Golgi Apparatus
   Compartment in which proteins are sorted
    and modified
   Stack of membrane-bound vesicles which
    package substances to be transported
    around the cell
The Lysosomes
   Small, round structures with a membrane
   Break down larger food molecules into smaller
       Digestion
   Attack “foreign bodies”
       Protection
   Digest old cell parts
   Not too common in plants
The Vacuoles
   Fluid-filled sacs found
    in both plants and
       Plants usually have few
        larger vacuoles
       Animals usually have
        smaller vacuoles
   Store food, water,
       Plants need to store
        large amounts of food

To top