Transcript Cell Organelles - Ms. Poole`s Biology

How do prokaryotic (bacteria)
cells reproduce?
simulation (sim u ‘la shen) (noun) - a
controlled model of a situation used to study it
Meteorologists run simulations of the
atmosphere in order to predict the weather
Binary Fission or Asexual
Reproduction
Cell Organelles!
Cell Membrane
• Also called plasma membrane
• Protects and supports the cell
• Controls what enters and
leaves the cell
• Lipid Bilayer (what does this
mean??)
• Found in all cells –
prokaryotes and eukaryotes!
Cell Wall
• Found in eukaryotic plant
and protist cells; also in
prokaryotes
• Adds protection, rigidity,
and support
• Outside of cell membrane
• Made of cellulose (a
polysaccharide!)
• Allows water and
dissolved substances to
pass through.
The Nucleus
• Controls most activities
in the cell
• Contains DNA – the
coded instructions for
making proteins & other
molecules for the cell
• The nuclear envelope has
nuclear pores, where
things can enter or leave
See?
Nucleolus
• Small, dense
region in the
middle of the
nucleus
• This is where
ribosomes are
formed.
Cytoplasm
• Clear fluid within cell
that contains all
organelles
• Moves materials
throughout the cell
It’s the light
blue/gray
stuff in this
picture
Ribosomes
• Makes proteins in the cell
• May be free in cytoplasm
or attached to ER
In prokaryotes and eukaryotes
• Proteins are vital to lifeall cells must produce
them!!!
• Stacks of membranes
used for storing,
modifying, or packaging
chemicals
• Packaged chemicals can
be stored inside the cell
or secreted outside the
cell
• Cells that make saliva or
mucus have many Golgi
bodies
Golgi
Apparatus
Endoplasmic Reticulum
• Series of folded
membranes that form
sacs or tubes
• Rough ER has
ribosomes attached
Smooth vs. Rough ER
Smooth ER
Rough ER
•Smooth - no
ribosomes!
•Ribosomes
make it look
rough or
bumpy
•Synthesizes
(makes) lipids
•Detoxifies
drugs
•Ribosomes
synthesize
(make)
proteins, so
the Rough ER
is where this
happens!
Lysosomes
• Found near Golgi
• Contain digestive
enzymes to digest
unwanted particles
• Help white blood cells
to destroy bacteria
• Clean-up crew!
censored!!!
Vacuoles
• Store food, water, or
waste materials
• Plant cells have large
vacuoles
Vacuoles and lysosomes
working together!
Amazing! Astounding!
Chloroplasts
• Found in eukaryotic plant
cells & some protist cells
• Chloroplasts capture
light energy and convert
it into chemical energy
during photosynthesis
Mitochondria
• Energy producers – the
“powerhouse” of the cell!
• Convert chemical energy into
useable energy
• Many mitochondria in muscle
cells – why??
• Found in all eukaryotes, including
animal & plant cells
• Contain DNA from ovum – so all
your mitochondria are from your
mom!
Endosymbiotic Theory
• Mitochondria are the result of endocytosis
of aerobic bacteria
• Chloroplasts are the result of endocytosis of
photosynthetic bacteria
• Endocytosis: A substance gains entry into a
cell without passing through the membrane
Evolution of Mitochondria
Evolution of Chloroplast
Does the timing make sense?
• Prokaryotes were
present before
eukaryotes
Evidence for Endosymbiotic Theory
• Mitochondria and chloroplasts have many
characteristics of free living bacteria:
1- contain DNA similar to bacterial DNA
2- have ribosomes of similar size and
structure to those of bacteria
3- reproduce by binary fission like bacteria
Cytoskeleton
• Overlapping network of
filaments and fibers that
support the cell and help
it maintain its shape
• Can also help cells move
• Microfilaments and
microtubules
• Centrioles help to
organize the cell
during cell division
Centrioles
• They migrate to
either side of the
cell and help to pull
it apart
• Only found in
animal cells!
Centrioles are made of microtubules
Types of Eukaryotes:
Animal vs. Plant Cells
Animal cells
Plant cells
• No cell walls (only
cell/plasma membrane)
• No chloroplasts
• Many small vacuoles
for storage
• Cell wall (gives
rectangular shape) and
cell/plasma membrane
• Chloroplasts for
photosynthesis
• One large central
vacuole
Plant Cell
Animal Cell
The End
I
Cells!