The Cell Organelles
and Organization
•The mixture of
compounds forming a
jellylike substance where
the nucleus, cytoplasm,
and cell membrane are
located is called
protoplasm. Suspended in
the protoplasm are the
organelles acting like little
organs that carry out
specific functions.
ORGANELLES FOR PROTECTIONS
Cell membrane
• Also known as the plasma membrane or
plasmalemma.
• It is a double-layered membrane that
encloses the cell.
• It is made up of a phospholipid bilayer,
with proteins and carbohydrates scattered
within inside it like a little mosaic.
• The proteins in the membrane also help
the cell communicate with other cells
(cell-to-cell interaction.
Cell wall
•The additional boundary
outside the cell
membrane. It surrounds
the cells of plants, fungi,
bacteria and some
protozoans, making them
rigid.
•Cell walls are made up of
cellulose and chitin and
other proteins.
Nucleus: Command Center
•A dark-stained part of the
protoplasm enclosed by a
nuclear membrane or nuclear
envelope.
•It controls all the activities of
the cell, it contains
deoxyribonucleic acid (DNA)
arranged into a network of long,
thread-like structures called
chromatin
Organelles for Energy processing
Mitochondria
•They are smalldoubled-membraned and
spherical or sausage-shaped organelles
involved in the production of energy.
•It produces adenosine triphosphate (ATP).
•This is popularly known as the
powerhouse of the cell
•Mitochondria have an inner membrane
that is folded into cristae to increase
surface area allowing more ATP
production.
Plastids
•Double-membraned organelles in plant
cells, bacteria and some protozoans.
•Chloroplasts are the most common
plastids found in green plants. They
contain green chlorophyll. Chloroplasts
trap energy from the sun during
photosynthesis, a process where cell
manufactures its own food.
•Chromoplasts are plastids that give
yellow and orange colors to flowers
and fruits.
•Leucoplasts are colorless plastids that
store carbohydrates, proteins and fats.
Organelles for Manufacturing Products
Ribosomes
•Are small granular structures that are
made up of ribonucleic acid (RNA) and
proteins. RNA is produced in the
nucleolus and enters the cytoplasm
through the nuclear pore located in
the nuclear membrane.
•It produce proteins from RNA.
Endoplasmic Reticulum
• A membranous structure that
forms a network of canals
through which proteins and
other molecules are
transported.
• Rough endoplasmic reticulum
(RER) is an organelled to which
most of the ribosomes are
attached.
• Smooth endoplasmic reticulum
(SER) is a branching canal
without ribosomes that
transports large molecules
inside the cell.
Golgi Apparatus or Golgi
Complex
• Another membranous
organelle forming a
stack of flattened sacs
located close to the
ER
• The Golgi apparatus
modifies proteins
produced in the
ribosomes that are
embedded in the RER.
Organelles for Storage and Breakdowns
Vacuoles and Vesicles
• Vacuoles store materials such as water,
carbohydrates, proteins and salts. Most plant
cells have a large fluid-filled vacuole at its
center.
• The pressure inside the vacuole allows the
plant to maintain turgidity, which helps the
plant stand erect and support its stem and
leaves.
• Contractile vacuoles allow the cell to pump
excess water
Lysosomes
•Are membrane bound organelles
that contain different hydrolytic
enzymes, called lysozymes.
•They breakdown carbohydrates,
proteins and nucleic acids. They
also digest bacteria, viruses and
damaged cell. The membrane of
lysosomes is a lipid bilayer that
prevents the lysozymes from
destroying other parts of the cells
Structure for Support and Communication
Cytoskeleton
• A network of filaments with varying
degrees of thickness and different
protein components.
• It serves as the “bones and muscles” of
the cells.
• Microfilaments responsible for giving
cell shape and form. They are also
involved in the constriction of
cytoplasm during cell division.
• Microtubules serve as the anchor of
organelles in the cell.
• Centrioles and spindle fibers involved in
cell division.
Cell Surfaces and Junctions
Plasmodesmata
•They plays an
important role in
sharing of water,
nourishment,
and chemical
messages among
plant cells.
•Tight junctions - join two cells tightly
together, forming a leakproof.
•Anchoring junctions - act like rivets or
screws, together with cytoskeletal fibers
to form strong sheets.
•Gap junctions – play a role similar to that
of plasmodesmata, allowing small
molecules to flow between adjacent cells.
•Extracellular matrix (ECM) - which acts as
a glue to hold cells together in tissues. The
ECM of plant cells is the cell wall.
Monday Activity
“Cell Model Making”
Direction: Create a model of a cell out of
anything. You may use everything in
making your cell model (clay,popsickle
sticks, styrofoam chocolates, Nips,
gummies, gums, candies etc.)
“Cell Model Making Rubrics”
Originality – 30%
Creativity- 20
Appearance – 30
Completeness -20