Download The Cell - Old Saybrook Public Schools

11/12/14
What should you know?
The Cell
•  All of it!
Important Players
•  Robert Hooke (1665)
–  Coined the term “cell”
•  Anton van
Leeuwenhook (1674)
–  “animalcules”
•  Matthias Schleiden
(1838)
–  All plants made of cells
•  Theodor Schwann
(1839)
Cells are
bitchin’
Animalcules
YAY!
The Cell Theory
•  All livings things are composed of cells
•  Cells are the basic structural and
functional units of living things
•  New cells are produced from existing
cells
–  All animals made of
cells
•  Robert Virchow (1855)
–  All cells come from
cells
What do all cells have in
common?
•  Cell membrane
–  Thin, flexible barrier
–  “Gatekeeper”
•  Hereditary material
–  DNA
•  Cytoplasm
–  Fluid within the cell
•  Organelles-not
membrane bound in
prokaryotes
–  Helps the cell to
function
Two categories of cells
Prokaryote
•  No nucleus
•  No membrane covered
organelles
•  Circular DNA
•  Bacteria
•  Less DNA
•  Always cell wall
•  Older
•  Simple
•  Smaller
Eukaryote
•  Nucleus
•  Membrane covered
organelles
•  Linear DNA
•  All other cells
•  More DNA
•  Sometimes cell wall
•  Younger
•  Complex
•  Bigger
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Cell Structures
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Cell Wall
•  Lies outside the cell
membrane
•  Allows H2O, O2 and
CO2 to pass
•  Main function is to
provide support and
protection
•  Compose of CHO and
protein
Cell wall
Nucleus
Nucleolus
Nuclear envelope
Cytoskeleton
Centriole
Ribosomes
Endoplasmic reticulum (ER)
Golgi apparatus
Lysosomes
Vacuoles
Chloroplast
Mitochondria
Cell wall vs no cell wall
Cell
Wall
Cell
Membrane
–  Plant cell walls =
cellulose
Nucleus
•  Controls most cell
processes
•  Contains DNA
•  Chromatin/Chromosomes
•  Nucleolus
•  Nuclear envelope
Hereditary
Information
•  Chromatin
–  DNA bound to
protein, granular
material visible in
nucleus
•  Chromosome
–  condensed
chromatin apparent
when cell divides
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Nucleolus
Nuclear envelope
•  Small dense region
within the nucleus
•  Where ribosomes
are assembled
•  Double membrane
layer surrounding
nucleus
•  Sprinkled with
nuclear pores
–  Allows material to
move in and out of
nucleus
Nuclear
Envelope
Cytoskeleton
Microtubule
•  Network of protein
filaments that help the
cell to maintain its
shape
•  Aids in cell movement
•  Composed of
microtubules,
intermediate filaments,
and microfilaments
•  Hollow tubes of protein
•  Maintain shape
•  Allow a “track” for
organelles to travel on
•  Help to separate
chromosomes during
cell division
–  Centrioles (animals only)
•  Cilia & flagella
Intermediate &
Microfilament
Cytoskeleton
•  Long, thin fibers
•  Help cell movement
•  Smaller than
microtubule
•  Provide tough flexible
framework that
supports the cells
Microfilament
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Organelles in the cytoplasm
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Ribosome
•  Protein assembled
on ribosome
Ribosomes
ER
Golgi apparatus
Centriole
Lysosme
Vacuoles
Chloroplast
Mitochondria
ER – act as a
transport system
•  Smooth ER
Golgi Apparatus
•  Proteins made by rough ER are sent here
where CHO and lipids attached
–  Components of cell
membrane
assembled here
–  Prepared to be sent to their final destination
•  Rough ER
–  Proteins are
modified “spell
check”
Golgi
Lysosomes
The “Suicide Sac”
•  Organelle filled with
enzymes
–  Break down lipids,
CHO, and proteins
from food into particles
that can be used by the
cell
–  Break down old
organelles
•  Only found in animal
cells
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Centriole
•  Found within the
centrosome
–  Area where microtubules
are produced
•  Aid in cell division by
helping to move
chromosomes by
organizing spindle
•  ONLY ANIMAL CELL
Vacuoles
•  Structure used to
store water, salts,
proteins, CHO
•  Plants have a single
large vacuole
•  Contractile vacuole
–  Squeezes out extra
water in aquatic
unicellular organisms
Chloroplast
Mitochondria
•  Not in animal and
fungal cells
•  Site of photosynthesis
•  Two envelope
membrane
•  Stacks of
photosynthetic
“coins”
•  Chlorophyll
•  Use energy from
food to make ATP
–  Growth
–  Development
–  Movement
•  Two membranes
Endosymbiotic Theory
•  Eukaryotes evolved by a large
prokaryotic cell engulfing mitochondria
and chloroplasts
•  Evidence:
By Lynn Margulis
–  contain their own DNA necessary for their
proper function
–  Contain ribosomes
–  Reproduce via binary fission
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Animal
•  Lysosome
•  Centriole
•  Small vacuole
Small
Vacuole
Cell Categories
Plant
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Cell wall
Chlorophyll
Chloroplast
Large vacuole
PROKARYOTIC
EURKARYOTIC
Animal
Plant
Lysosome
Another look
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How much do you know?
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