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  THE CELL Structures and Parts
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Cell Theory
Anton Van Leeuwenhoek

Father of the Microscope Father to the term
"Cell"
Robert Hook
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Cell Theory
Matthias Schleiden 

• Botanist first to study plant cells.
• Studied animal cells first

Theodore Schwann
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Cell Theory

• Plants cells made other plant cells
• Animal cells made other animal cells

Rudolph Virchow
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Cell Theory
Schleiden and Schwann

• proposed the cell theory in 1838
• cell biology research was forever changed. 

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states that
Cell Theory
1. All life forms are made from one or more
cells. 
2. Cells only arise from pre-existing cells. 
3. The cell is the smallest form of life.
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Robert Hooke

• used a crude compound microscope to view a cork
  and seen honey comb shapes in 1665. 
• He coined the term cells since they reminded him
  of the small box cells Monks lived in.

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Study of Cells

•  Microscopes - magnify things not visible with
  human eyesight alone.
•   Anton Van Leeuwenhoek , used a single lens to
  view cells in the 1600s.

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Cell Theory

• 
  in the 1830s
• viewed organisms underneath microscopes and
  verified that all living things are made of cells.

Schleiden and Schwann
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Microscopes
Compound

• Microscope
• has a series of lenses that magnifies the object
  in steps.
• Microscope -
• electrons are aimed in a beam through a magnetic
  field to focus them then, through or over a
  specimen in a vacuum, and finally onto a screen
  where it forms a image.     

Electron 
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Size
Cell

• Cells have to be limited in size by natural
  laws. 
• enough to hold the essential
  components
• enough to accommodate nutrients
  received and disposed.

Large
Small
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Size
Cell

• Large cells have less surface volume relative to
  its size than small cells. 
• So the bigger the cell doesnt mean more
  effective. 
• The smaller cells can be serviced better by the
  cytoplasm.

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Cell Size

• Computer chip technology
• is similar to this natural phenomena.

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Size
Cell

• Eukaryote CELLS (PLANT, ANIMAL, PROTIST FUNGI)
• range from 10 micrometers to 100 micrometers in
  diameter.  
• PROKAROTE CELLS (BACTERIA)
• are a lot smaller and structurally simple  

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Cell Types

Prokaryote and Eukaryote
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Prokaryote

• is the first type of cell to evolve, there are NO
  internal organelle structures. 
• It has DNA and cytoplasm and most likely single
  celled.

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Prokaryote

• Bacterial Cells
• Capsules
• Act as cell walls
•  
• Circular DNA  
• Genetic information
• coiled DNA
• No membrane for nucleoid region.  

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Prokaryote

• Prokaryotic cells
• are small and structurally simple
• Simple membrane bound cytoplasm
• DNA 
• RNA
• All Bacteria cells are Prokaryotes 

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Eukaryote

• They can be single cell or multi-cellular
  organisms.
• Eukaryote - The second type of cell formed. 

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Eukaryote

• Complexity
• Organelles
• Nuclei
• Plants have cell walls
• Large Vacuole  

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Eukaryote

• Multi cellular and Unicellular types have
• Plant - multi
• Animal - multi
• Protist single and multi
• Fungi  - single and multi

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Cell Composition  

• Plasma membrane
•   Cytoplasm
•   Organelles
•   Nucleus
•   Cell Wall (only in plants)  

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Animal Plant Cell ORGANELLES

• Eukaryotic cells have functional compartments 
• NUCLEUS Contains
• DNA stores genetic information
• RNA transmits genetic information
•   Messenger  - mRNA
•    Transfer tRNA
•    Ribosomal - rRNA
• Ribosome - makes proteins
• Assembles amino acids into polypeptides
  polymers.

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Animal Plant Cell ORGANELLES

• Flagella motor transport of cell (Animal
  Protists)
• Centriole helps cell division (Animal)
• Lysosome breaks down particles. (Animal)
• Golgi Apparatus stores and packages
• Plasma Membrane regulates entry in to the cell
  and maintains homeostasis

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Animal Plant Cell Organelles

• Endoplasmic Reticulum
• Transport passage for the cells chemicals.
• Types of E.R.
•  Smooth no ribosomes 
• Rough with ribosomes

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Animal Cell Organelles

• Mitochondrion energy generator of the cell
  (battery)
• Cytoskeleton Supports the cells structure
• Microtubule comprises the cytoskeleton
•  Microfilament - comprises the cytoskeleton

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Plant Cell Organelles

• Cell Wall Composed of Cellulose
• Give strength and structure to plants
• Vacuole  - Storage
• Chloroplast Absorb sunlight for
  photosynthesis.

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Review Cell Theory  

• 1. All life forms are made from one or more
  cells.       
• 2. Cells only arise from pre-existing cells. 
       
• 3. The cell is the smallest form of life. Cells

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The Cell Theory 

• Schleiden and Schwann proposed the cell theory in
  1838,
• cell biology research was forever changed.