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Nucleus
 where genetic information is stored
 determines the structural characteristics of cell and how
it functions.
(a) Chromatin – uncoiled DNA
(b) Nucleolis – produces RNA used to make proteins
Ribosomes
 Has a large and small subunit made up of ribosomal
RNA and protein
 Free ribosomes – in cytoplasm, helps make proteins
that will be used in cell
 Bound ribosomes – bound to rough ER, helps make
proteins that will be sent to the outside of the cell or to
the plasma membrane
Rough Endoplasmic Reticulum (Rough ER)
 Takes proteins (which were made with the help of
bound ribosomes) and modifies and processes them
so they can be sent to the Golgi Apparatus.
Smooth Endoplasmic Reticulum (Smooth ER)
 Makes macromolecules such as lipids (e.g.
phospholipids), produces hormones and sends
materials to the plasma membrane or Golgi Apparatus
Golgi Apparatus
 Completes the processing of macromolecules (e.g.
lipids and proteins) to make them fully functional
 Sorts and packages macromolecules, so they are
ready for transport.
Transport Vesicles
 Membrane bound organelles that carry material to
different areas within the cell (e.g. carries proteins from
rough ER to Golgi, and from Golgi to cell membrane)
Mitochondria
 Site of respiration (where energy in macromolecules is
transformed into a useable form)
 (a) Cristae - folds of inner mitochondrial membrane –
increases the surface area for enzymes to make ATP
Chloroplast (plant cell only)
 Location of photosynthesis
 Contains chlorophyll (green pigment) that absorbs
sunlight and creates glucose
Lysosomes
 Contain digestive enzymes that break down
macromolecules or other large structures (e.g.
damaged organelles)
 Formed from the Endoplasmic Reticulum
Peroxisomes
 Breaks down large fatty acid chains and detoxifies
alcohol (found in liver, kidney, brain)
 Formed in the cytoplasm
 Peroxisomes are membrane-bound packets of oxidative enzymes. In plant cells,
peroxisomes play a variety of roles including converting fatty acids to sugar and
assisting chloroplasts in photorespiration. In animal cells, peroxisomes protect the
cell from its own production of toxic hydrogen peroxide. As an example, white
blood cells produce hydrogen peroxide to kill bacteria. The oxidative enzymes in
peroxisomes break down the hydrogen peroxide into water and oxygen.
Cytoskeleton (Actin, Intermediate Filaments,
Microtubules)
 Organizes location of organelles within cytoplasm
 Gives shape to the cell
 Allows movement of organelles throughout cell
Centrosome
 The centrosome, or MICROTUBULE ORGANIZING
CENTER (MTOC), is an area in the cell where
microtubules are produced. Centrosomes coordinates
activities of spindle fibers when cell divides
 Plant and animal cell centrosomes play similar roles in
cell division, and both include collections of
microtubules, but the plant cell centrosome is simpler
and does not have centrioles.
 Involved in the formation of cilia and flagella
Cilia
 Short, cylindrical
projections from cell that
produce wave-like motions
that move the cell in its
environment
 Moves particles out of the
lungs
Flagella
 Long projections produce
whip like motion to move
cell.
Centriole (animal cells only):
 Each centriole is a ring of nine groups of fused microtubules. There are
three microtubules in each group. Microtubules (and centrioles) are
part of the cytoskeleton. In the complete animal cell centrosome, the
two centrioles are arranged such that one is perpendicular to the other.
 During animal cell division, the centrioles replicate (make new copies)
and the centrosome divides. The result is two centrosomes, each with
its own pair of centrioles. The two centrosomes move to opposite ends
of the nucleus, and from each centrosome, microtubules grow into a
"spindle" which is responsible for separating replicated chromosomes
into the two daughter cells.
Cell Wall (plant cell only)
 Contains cellulose fibers
 Adds strength and rigidity to the cell
 Prevents cell from bursting in hypotonic environment
Vacuole:
Vacuole: A vacuole is a membrane-bound sac that plays
roles in intracellular digestion and the release of cellular
waste products. In animal cells, vacuoles are generally
small. Vacuoles tend to be large in plant cells and play
several roles: storing nutrients and waste products, helping
increase cell size during growth, and even acting much like
lysosomes of animal cells.
Central Vacuole (only in plant cells)
 The plant cell vacuole also regulates turgor pressure in the cell. Water
collects in cell vacuoles, pressing outward against the cell wall and
producing rigidity in the plant. Without sufficient water, turgor pressure
drops and the plant wilts.Storage space for water and other substances
(e.g. toxins that deter predators from eating it)

Most mature plant cells have one large central vacuole that typically
occupies more than 30% of the cell's volume, and that can occupy as
much as 80% of the volume for certain cell types and conditions
Websites:
http://www.cellsalive.com/cells/cell_model.htm
http://en.wikipedia.org/wiki/Vacuole