Transcript The Cell Theory!

The Cell Theory!
Leeuwenhoek
▫ Used a simple microscope
▫ First to see cells!
Robert Hooke
• Used a compound microscope
• Looked at cork- saw
• This reminded him of rooms in a monastery so
he called them “cells.”
T. Schwann
• Sounds like __________
▫ Swan!
• Concluded that all animals were made of cells.
M. Schleiden
• Concluded all plants were made of cells
Summary
*Hooke
Cells
*Schwann
Animals
*Schleiden
Plants
All those scientists contributed to:
• The Cell Theory
• What is a theory?
• A broad explanation that is testable, and has
been proved by multiple researchers.
• Components of it can be changed or improved
upon, without changing the overall truth of the
theory as a whole.
First Part of the Cell Theory
• All living things are made of
▫ cells
• They are either:
▫ Unicellular Consisting of only ONE cell
▫ Multicelluar Consisting of MANY cells.
Second Part of the Cell Theory
• A cell is the basic unit of life.
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Cells
Tissue
Organ
Organ system 
Organism!
• The beginning unit is always what?
▫ A CELL!
Third Part of the Cell Theory
• All cells come from pre-existing cells.
Muscle
Skin
Muscle
Muscle
Muscle
Skin
Muscle
Muscle
Skin
Muscle
INTRO TO CELLS
• You will need a separate sheet of paper to take
additional notes.
• http://videos.howstuffworks.com/hsw/9699cells-and-genetics-cell-theory-video.htm
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Intro to Cells!
• Cell organelles:
• “tiny organs”
Most important
•
nucleus!
Organelles we will be very familiar
with!
• Nucleus**
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▫ Nucleolus
Endoplasmic Reticulum (rough and smooth)
Ribosomes**
Golgi Apparatus
Lysosomes
Plasma (cell) membrane**
Vesicles
Mitochondria**
Cytoplasm (cytosol)
Cytoskeleton
▫ Centrioles
• Vacuoles
• Chloroplasts**
• Cell Wall**
Two categories of cells:
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Prokaryotes
No nucleus
Majority are unicellular
Simple- 1-2 organelles
1 job at a time
Bacteria (eu- and
archaea-)only
• Eukaryotes
• Nucleus
• Majority are multicellular
• Complex- 10-12 organelles
• Good at Multitasking
• Plants/animals/fungi/
protists
**THEY BOTH HAVE DNA AND RIBOSOMES!!!**
PROKARYTIC CELLS LACK
MEMBRANE BOUND ORGANELLES
Escherichia coli (E. coli)
Prokaryotic Cell
Eukaryotic Cells
Fungi
Animal
Plant
Protist
Semi (selectively) Permeable
• Semi▫ Some
• Selectively▫ choosey
• Permeable▫ allows to pass
• Selectively Permeable▫ chooses what it allows to pass through (Does this
by active and passive transport).
Cell Membrane
AKA “Plasma Membrane”
AKA
Thephospholipid
outer boundary of bilayer
a cell- skin
• Job:
▫ To maintain homeostasis
 To regulate what goes in and out of a cell
• What is homeostasis?
▫ Internal balance- keeping things happy
CARBOHYDRATE
PROTEIN MOLECULE
PROTEIN MOLECULE
PROTEIN MOLECULE
LIPID
BILAYER
A.
Water- loving (outside
of cell- touches water)
B.
Water- fearing (inside of
sandwich- never touches water)
POLAR
HEADS
NONPOLAR
TAILS
Fluid Mosaic Model*
• Fluid Flexible
• Mosaid different parts
• Model  representation
Function of:
• Proteins in the membrane:
▫ Transport molecules in and out of the cell.
• Lipids in the membrane:
▫ Creates a barrier between the cell and the watery
environment that is surrounding.
• Carbohydrates in the membrane:
▫ Chemical signals and cell communication
ALL CELLS…
• … HAVE DNA AS THEIR GENETIC
MATERIAL (nucleus=euk or nucleoid=prok)
• … HAVE A CELL MEMBRANE
• … HAVE RIBOSOMES
• … HAVE CYTOPLASM
• http://videos.howstuffworks.com/hsw/6051cells-cell-walls-and-cell-membranes-video.htm