Transcript Microtubules and Microfilaments

Plasma Membrane
• Helps maintain Homeostasis
• Present in all cells
• Flexible boundary between the cell and its
environment to allow nutrients and wastes
to enter and exit
Cytoskeleton
• Supportive network of proteins that helps to form
a frame work for cells
– Just like your skeleton supports YOU!
• Composed of rods/filaments (Microtubules and
Microfilaments) that can be rearranged to meet
the needs of the cell
– Think of poles that maintain the shape of a tent.
• They also help to anchor and support many
organelles and provide a highway system
through which materials move in and out of the
cell.
• Found in BOTH!
Microtubules/Microfilaments
• Thin hollow tubes made
of proteins
• Acts as “tracks” to move
organelles
• Smaller, solid protein
fibers
– Think of small threads
• Enable the cell to move
and divide
• Help muscles contract and
relax
Work together
Both work to anchor and support many organelles
Provides a highway system for materials to move
within a cell
Microfilaments/Microtubules
Cytoplasm
• fills the space between
the nucleus and the cell
membrane
• Clear, gelatinous fluid
portion is called cytosol
and is mainly water
• Location of all other
organelles
• Found in all Cells
Nucleus
• Cell Control Center
• Contains the
directions to make
proteins
• Two main jobs is to
protect the DNA
and make sure that
DNA is always
available for use.
• Found in all cells
Nuclear Membrane and
Nuclear Pores
• Located outside of the
nucleus
• Also called Nuclear
envelope
• Made up of a double
membrane containing two
phospholipid bilayers
• Contains small nuclear
pores
– Allow substances to pass from
the nucleus to cytoplasm
Nucleolus
• Located within the
nucleus
• Responsible for
making ribosomes
Endoplasmic Reticulum
• A folded membrane that forms a network of
interconnected compartments in the
cytoplasm
• The location of cellular chemical reactions
• Found in Both types of cells
• Rough ER – contains ribosomes that are
attached to the surface, it is involved in the
transport, storage, making and modifying of
proteins.
• Smooth ER- production and storage of lipids,
contains NO ribosomes
Ribosomes
• Site of protein synthesis (make proteins)
– They link amino acids together
• Can be found floating in the cytoplasm,
BUT most of the time they attach to the
Endoplasmic Reticulum
• Found in all cells
Golgi Apparatus
• Closely stacked,
flattened membrane
sacs
• Modify, collect, and
sort proteins into
packages and
distributes proteins
produced by the cell
• Found in both plants
and animals
vesicles
• General name for little
membrane-bound sacs that
transport materials from
place to place in the cell
• Short-lived, they form and
break-down as needed
• Example: after a protein is
made in the ribosome, part
of the ER will pinch off and
form a vesicle to transport
the protein to the golgi
apparatus.
Mitochondria
• Power House of the
cell
• Produces a usable
form of Energy for
the cell
• Found in both plants
and animals.
Vacuole
• Fluid filled sac used to
temporarily store food,
water, enzymes, and
waste
• Singular and large in
plant cells, small and
numerous in animal
cells
Lysosome
• Contains digestive enzymes which help
them to digest excess or worn-out cell parts,
food and invading viruses and bacteria
• More numerous in animal cells.
Centrosome & Centriole
• Found in animal cells and some
algae
• Small region of the cytoplasm that
produces microtubules
• Contains small structures called
centrioles
–
–
–
–
Occur in pairs
Made of microtubules
Help with Cell Division
Organize microtubules to form cilia
and flagella
Flagellum
&
Cilia
• Made of microtubules • Short numerous
projections
• Aid in cell locomotion
and feeding (help to
• Look like hairs
move liquids past a
• Function like oars in a
cell)
rowboat
• Longer than cilia
• Aid in cell locomotion
• Move with whip-like
and feeding (help to
motion
move liquids past a
cell)
• Usually only has 1-2
flagellum
•Found in Some Animal Cells
Flagellum
& Cilia
Cell Wall
• Firm, protective, supportive structure that gives
the cell its shape
– Made of cellulose
• Porous –there are channels that allow all
molecules to enter through it.
• Found in most bacteria, fungi, algae and plants
Chloroplasts
• In inner membrane there
are disc-shaped sacs
called thylakoids that
contain chlorophyll
– which is a green
pigment that traps
Energy from the Sun
• Give plants their green
color (only in plants!)
• Produce food by capturing
light energy and
converting it into chemical
energy.