Download Review: parts of a microscope history of cell theory different types of

Review:
­ parts of a microscope
­ history of cell theory
­ different types of microscopes
Sep 25­9:00 AM
Prokaryotic and Eukaryotic Cells
(a) Prokaryotic Cells
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do not contain a nucleus (bacteria)
have no membrane bound organelles their DNA is concentrated in a area known as the nucleoid
Sep 25­9:01 AM
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(b) Eukaryotic Cells
­ cells that contain a nucleus (nerve cell)
­ the nucleus is an enclosed region that separates the DNA from the rest of the cell contents
­ eukaryotes contain specialized structures called organelles
Sep 25­9:05 AM
Classification of Eukaryotes
­ eukaryotic cells can be divided into two types; animal and plant cells
­ animal and plant cells share many organelles but there are some differences
(1)
Plant cells have a cell wall, animal cells do not
(2)
Plant cells have a large central vacuole, animal cells have many smaller ones
(3) Plant cells contain chloroplasts which help in photosynthesis, animal cells do not
(4)
Plant cells tend to be larger and more rectangular
Sep 25­9:09 AM
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Sep 25­9:16 AM
Typical Cell Organelles
1. Cell Membrane:
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the thin membrane that separates a cells contents from its outside environment
also controls the movement of material into and out of the cell
the cell membrane is made up mostly of lipids (fats) and protein
Sep 25­9:16 AM
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2. Cell Wall
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found only in plant cells
rigid structure that surrounds the inner cell membrane
protects and supports the cell
allows material to pass into and out of the cell through pores
consists mostly of cellulose and fibre
Sep 25­9:22 AM
3. Cytoplasm:
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the gel­like chemical environment inside of a cell membrane
made mostly of water
contains materials that create the chemical environment in which the cells organelles can function
Sep 25­9:26 AM
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4. Nucleus:
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­ the command center of the cell
contains the cells DNA and RNA
center of protein synthesis
surrounded by a double membrane which contains nuclear pores which allow material to enter and exit
Sep 25­9:30 AM
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