Download File chapter 7

Chapter 7 Cell Structure
http://content.answers.com/main/content/wp/en-commons/thumb/7/70/300px-FluorescentCells.jpg
Chapter 7 Vocabulary
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7.
8.
Cell wall
Cell membrane
Chloroplasts
Cilium
Eukaryote
Flagellum
Magnification
Mitochondrion
9. Prokaryote
10. Phospholipid
11. Lipid bilayer
12. Organelle
13. Selectively Permeable
14. Lysosome
15. Cell theory
Animal Cell
Animal Cell
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1. Nucleolus
2. Nucleus
3. Ribosome
4. Vesicle
5. Rough ER
6. Golgi Body
7. Cytoskeleton
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8. Smooth ER
9. Mitochondria
10. Vacuole
11. Cytoplasm
12. Lysosome
Plant Cell
Plant Cell
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A. Nucleus
B. DNA
C. Nucleolus
D. Nuclear Pore
E. Rough ER
F. Smooth ER
G. Central Vacuole
H. Cytoskeleton
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I. Chloroplasts
J. Cell Wall
K. Cell membrane
L. Mitochondria
M. Vesicle
N. Golgi Apparatus
7-1 Objectives
• List the three parts of the cell theory.
• Determine why cells have to be relatively
small.
• Compare the structure of prokaryotic cells to
that of eukaryotic cells.
Discovery of Cells
• Robert Hooke
– Looked at non-living cells in cork
using a crude microscope in 1665
– Called them cells because they
reminded him of a monk’s room
• Anton van Leeuwenhoek
– First to observe living organisms
(in pond water and bacteria from
his own mouth)
http://www.arsmachina.com/images/hooke.jpg
http://askabiologist.asu.edu/research/buildingblocks/images/hookecorkS.jpg
Microscopes
Light Microscope
• Sends light through a sample
Electron Microscope
• Sends beam of electrons through a
sample
• Use stains to make structures
visible
• Have to chemically preserve
samples = can’t be living!
• Can magnify up to 1000x to look
at cells as small as 1 millionth of
a meter
• Can look at things smaller than
cells i.e. viruses, DNA
ADD PICTURES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Cell Theory
1. All living things are
made up of cells
2. Cells are the basic
units of structure and
function in organisms
3. All cells arise from
other living cells
http://peer.tamu.edu/curriculum_modules/Cell_Biology/module_1/levels%20of%20organization.jpg
Why are cells small? Why can’t I
have a cell the size of a minivan?
http://www.eatel.net/~dacinc/minivan.jpg
Cells Must Be Small
• All substances that
enter or leave the cell
must cross the cell’s
surface
• The cell needs to
maintain a high
surface area to
volume ratio
• Large cells cannot take
in nutrients and get
rid of waste fast
enough for the cell to
survive.
http://library.thinkquest.org/C006669/media/Biol/img/surface_area_to_volume_ratio.gif
Common Features of All Cells
1. Cell membrane
A. keeps cell conditions
different from outside
environment
B. regulates what enters
or leaves the cell
2. Cytoplasm
A. inside the cell
membrane and
outside the nucleus
B. Jell-O like substance
http://www.daylilies.org/ahs_dictionary/cytoplasm.gif
Common Features of All Cells
3. Cytoskeleton
A. Support for
organelles
4. Ribosomes
A. Help make proteins
http://www.uic.edu/classes/bios/bios100/lecturesf04am/cytoskeleton.jpg
Prokaryotic vs Eukaryotic
http://www.phschool.com/science/biology_place/biocoach/images/cells/allcell.jpg
Prokaryotic cells do not contain
internal compartments
Prokaryotes
A. No nucleus and no
compartments
B. 3.5 billion years old
http://english.pravda.ru/img/2005/11/bacteria.jpg
Eukaryotic cells are well organized
Eukaryotes
A. Have a nucleus which
holds DNA
B. Organelles carry out
specific activities
Prokaryotes
Eukaryotes
7-1 Review Questions
1. Why do cells have to be small?
2. Name four structures that are common to
all cells.
3. What is the difference between a
prokaryotic and eukaryotic cell?
7-2 Objectives
• Describe the role of the nucleus in cell
activities.
• Analyze the importance of cell organelles in
protein production.
• Summarize the importance of mitochondria in
eukaryotic cells.
• Identify three structures in plant cells that are
absent in plant cells.
How is a cell like a factory?
Nucleus – “The Boss”
Directs All Cell Activities and Stores DNA
1. Nuclear envelope –
surrounds nucleus
2. Nuclear pores –
helps substances
move into and out
of the nucleus
3. Nucleolus – helps
assemble
ribosomes
http://spectorlab.cshl.edu/images/NucleusModel.jpg
DNA (“Blueprint”) is Stored
in the Nucleus
A. When the cell is not
dividing – chromatin
B. When cell is dividing –
condenses into
chromosomes
http://homepage.smc.edu/hgp/images/cell-to-DNA.jpeg
The Cell Membrane – “Security”
Controls what enters and leaves the cell
A. Selectively
Permeable = only
lets certain things
through
B. Proteins in the
membrane “check
ID”
http://sun.menloschool.org/~cweaver/cells/c/cell_membrane/fluid_mosaic.jpg
Production of Proteins – “Manufacturing”
1. Ribosomes
– Make proteins that remain
in the cell
2. Rough Endoplasmic
Reticulum (ER)
– Makes proteins that are
exported from the cell or to
specialized organelles
http://micro.magnet.fsu.edu/cells/endoplasmicreticulum/images/endoplasmicreticulumfigure1.jpg
“Manufacturing”
3. Smooth ER
– no ribosomes
– makes lipids and
breaks down toxins
• Vesicles (“Mail Carriers”)
– membrane bound sacs
that transport proteins
http://www.nsf.gov/news/overviews/biology/assets/interact07.jpg
http://www.unipv.it/webbio/anatcomp/freitas/2006-2007/smooth%20&%20rough.jpg
Golgi Apparatus
“Customization and Shipping”
Gets proteins ready for transport
1. Proteins made in the
Rough ER move to
Golgi apparatus
2. Enzymes modify the
proteins
3. Then they are
enclosed in a new
vesicle for transport
http://www.mie.utoronto.ca/labs/lcdlab/biopic/fig/4.12.jpg
Lysosomes – “Maintenance”
Function in digestion and waste removal
A. Made by Golgi apparatus
B. Contain enzymes for
digestion
C. Recycle a cell’s used parts
http://sun.menloschool.org/~cweaver/cells/e/lysosomes/brittanica.jpg
http://student.ccbcmd.edu/~gkaiser/biotutorials/eustruct/images/phagocyt.gif
Mitochondria – “The Powerhouse”
Converts sugar to energy (ATP)
A. Inner membrane is
highly folded
– creates more surface
area
– many complex
chemical reactions
occur here
B. Muscle cells have a lot
of mitochondria
http://www.octc.kctcs.edu/gcaplan/anat/images/Image337.gif
Mitochondria – “The Powerhouse”
http://micro.magnet.fsu.edu/cells/mitochondria/images/mitochondriafigure1.jpg
Mitochondria and Chloroplasts have
their own DNA!
Mitochondrial DNA
• Inherited through
mother
• Mitochondria could
once have been freeliving organisms
=> Endosymbiosis
1) can explain the origins
of eukaryotic cells
2) one small cell came to
live inside another
http://www.accessexcellence.org/RC/AB/WYW/lander/images/inheritance_chart.gif
Endosymbiosis
http://www.sirinet.net/~jgjohnso/endosymbiosis.jpg
Plants cells have certain structures
that Animal cells lack
1. Cell Wall
A. Supports and
protects
B. Contains cellulose
http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG
2. Chloroplasts – “Solar Power!”
Converts sunlight into carbohydrates
A. Found in plants and
green algae
B. Like mitochondria,
contain their own
DNA
http://micro.magnet.fsu.edu/cells/chloroplasts/images/chloroplastsfigure1.jpg
3. Central Vacuole – “Storage”
Stores water and other substances
A. When full, makes
cell rigid
B. Enables plants to
stand upright
http://www.progressivegardens.com/knowledge_tree/plantcell.jpg
Review Questions
1. What is the difference between Rough and
Smooth ER?
2. What is the function of mitochondria?
3. Which cell organelle is the shipping and
packaging center for the cell?
4. What are the functions of lysosomes?
5. Why do mitochondria and chloroplasts
have their own DNA?
6. Name three structures found in plant cells
that are not found in animal cells