Week 10-11 Cells and Cell Theory
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VIEW A CELL DIAGRAM
The Cell Theory
Anton Van Leeuwenhoek
Father of the Microscope
Robert Hook
o Father to the term "Cell"
Matthias Schleiden 
o Botanist studied plant cells First
Theodor Schwann
o Studied animal cells first
Rudolph Virchow
o Said plants cells made plant cells
o Animal cells made animal cells

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

The cell theory states that: 

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

o 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.

Cell Types

? Prokaryote 
?  Eukaryote

o Prokaryote ? is the first type of cell to evolve, it has not internal organelle structures.  It has DNA and cytoplasm and most likely single celled.
Prokaryote
? Prokaryotic cells are small and structurally simple
? Simple membrane bound cytoplasm
? DNA 
? RNA
? bacteria
 

Eukaryote
o Eukaryote - The second type of cell formed. 
? Complex
? Organelles
? Nucleus
? Plants have cell walls
? Multicellular and unicellular types 
? Membrane
? Cytoplasm
? Plant
? Animal
 
Cell Types

Prokaryote and Eukaryote

Prokaryote ? is the first type of cell to evolve, it has not internal organelle structures.  It has DNA and cytoplasm and most likely single celled.

Eukaryote ? is more evolved and complex than its predecessor, it has internal structures (organelles) the largest being the nucleus where DNA is held.   They can be single cell or multi-cellular organisms.

 Cell Composition

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

 Cell Size
Cells have to be limited in size by natural laws.  It must be large enough to hold the essential components and small enough to accommodate nutrients received and disposed. 

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

Computer chip technology is a parallel to this natural manifestation.

PLANT AND ANIMAL CELLS, range from 10 micrometers to 100 micrometers in diameter.
 

Prokaryotic cells are small and structurally simple

 No Nucleus

 Coiled DNA (Nucleoid Region)
  No membrane around nucleoid region

 Ribosomes 
  Assemble amino acids into polypeptides
   Polymers make protiens.
  RNA
   Messenger 
   Transfer
   Ribosomal

Bacterial Cell Wall

 Capsule

 Circular DNA

 Bacteria Flagella

Eukaryotic cells have functional compartments 

Animal

Flagellum

Centriole

Lysosome

Golgi Apparatus

Plasma Membrane

Endoplasmic Reticulum
 Smooth
 Rough
Peroxisome

Mitochondrion

Cytoskeleton

Microtubule

 Microfilament 

Nucleus

  Plant
Golgi Apparatus

Plasma Membrane

Endoplasmic Reticulum
 Smooth
 Rough
Peroxisome

Mitochondrion

Cytoskeleton

Microtubule

 Microfilament 

Nucleus

   Cell Wall
  
   Central Vacuole

   Chloroplast

The Cell Theory 
  When Scheiden and Schwann proposed the cell theory in 1838, cell biology research was forever
  changed. The cell theory states that: 

      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 Chapter 8

Study of Cells

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

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.

Schleiden and Schwann in the 1830ís view organisms underneath microscopes and verified that all living things are made of cells.

Compound Microscope ? has a series of lenses that magnifies the object in steps.

Electron  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.