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8/2/2019 Cell Parts and Its Functions
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Animal cell
Animal cells are typical of the eukaryotic cell, enclosed by a plasma membrane and containing a
membrane-bound nucleus and organelles. Unlike the eukaryotic cells of plants and fungi, animal cells do
not have a cell wall. This feature was lost in the distant past by the single-celled organisms that gave riseto the kingdom Animalia. Most cells, both animal and plant, range in size between 1 and 100
micrometers and are thus visible only with the aid of a microscope.
The lack of a rigid cell wall allowed animals to develop a greater diversity of cell types, tissues, and
organs. Specialized cells that formed nerves and musclestissues impossible for plants to evolvegave
these organisms mobility. The ability to move about by the use of specialized muscle tissues is a
hallmark of the animal world, though a few animals, primarily sponges, do not possess differentiated
tissues. Notably, protozoans locomote, but it is only via nonmuscular means, in effect, using cilia,
flagella, and pseudopodia.
Most animal cells are diploid, meaning that their chromosomes exist in homologous pairs. Different
chromosomal ploidies are also, however, known to occasionally occur. The proliferation of animal cells
occurs in a variety of ways. In instances of sexual reproduction, the cellular process ofmeiosis is first
necessary so that haploid daughter cells, orgametes, can be produced. Two haploid cells then fuse to
form a diploid zygote, which develops into a new organism as its cells divide and multiply.
http://micro.magnet.fsu.edu/cells/animals/animalmodel.html8/2/2019 Cell Parts and Its Functions
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CELL PARTS AND ITS FUNCTIONS
CENTRIOLES DESCRIPTION FUNCTION
Are cylindrical structures that are
composed of groupings
ofmicrotubules arranged in a 9 +
3 pattern. The pattern is so
named because a ring of nine
microtubule "triplets" are
arranged at right angles to one
another. They are found
in animal cells.
Centrioles help to organize the
assembly of microtubules
during cell division. They
replicate during
the interphase stage
ofmitosis and meiosis. It is also
called basal bodies form cilia
and flagella.
GOLGI BODY
The Golgi apparatus (GA), also
called Golgi body or Golgi complex
and found universally in both plant
and animal cells, is typically
comprised of a series of five toeight cup-shaped, membrane-
covered sacs called cisternae that
look something like a stack of
deflated balloons. In some
unicellular flagellates, however, as
many as 60 cisternae may combine
to make up the Golgi apparatus.
The Golgi apparatus is often
considered the distribution and
shipping department for the cell's
chemical products. It modifies
proteins and lipids (fats) thathave been built in the
endoplasmic reticulum and
prepares them for export outside
of the cell or for transport to
other locations in the cell.
http://biology.about.com/od/mitosisglossary/g/microtubules.htmhttp://biology.about.com/od/cellbiology/ss/animal_cells.htmhttp://biology.about.com/od/mitosis/ig/Mitosis-Image-Gallery/Interphase.htmhttp://biology.about.com/od/mitosis/ss/mitosisstep.htmhttp://biology.about.com/od/meiosis/ss/meiosisstep.htmhttp://biology.about.com/od/cellanatomy/a/aa050208a.htmhttp://biology.about.com/od/cellanatomy/a/aa050208a.htmhttp://biology.about.com/od/cellanatomy/a/aa050208a.htmhttp://biology.about.com/od/cellanatomy/a/aa050208a.htmhttp://biology.about.com/od/meiosis/ss/meiosisstep.htmhttp://biology.about.com/od/mitosis/ss/mitosisstep.htmhttp://biology.about.com/od/mitosis/ig/Mitosis-Image-Gallery/Interphase.htmhttp://biology.about.com/od/cellbiology/ss/animal_cells.htmhttp://biology.about.com/od/mitosisglossary/g/microtubules.htm8/2/2019 Cell Parts and Its Functions
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LYSOSOMES Lysosomes are
cellular organelles that contain
acid hydrolase enzymes to break
down waste materials and cellular
debris. These enzymes are
typically hydrolytic and can digest
cellular macromolecules.
They are made by the
endoplasmic reticulum and Golgi
complex. They are more than
likely formed by budding from the
"shipping" department of a Golgi
complex. They are found in animal
cells, while in yeast and plants the
same roles are performed by lytic
vacuoles.
The name lysosome derives from
the Greek words lysis to
separate and soma body. They
are frequently nicknamed
"suicide-bags" or "suicide-sacs" by
cell biologists due to their role
in autolysis
Lysosomes digest excess or
worn-out organelles, food
particles, and
engulfviruses or bacteria.
The membrane around a
lysosome allows the digestive
enzymes to work at the
4.5 pH they require. Lysosomes
fuse with vacuoles and dispense
their enzymes into the vacuoles,
digesting their contents.
CILIA AND FLAGELLA Cilia and flagella are motile
cellular appendages found in mostmicroorganisms and animals, but
not in higher plants. cilia and
flagella are essential for the
locomotion of individual
organisms. Protozoans belonging
to the phylum Ciliophora are
covered with cilia, while flagella
are a characteristic of the
protozoan group Mastigophora.
In multicellular organisms, cilia
function to move a cell or groupof cells or to help transport fluid
or materials past them. Among
other tasks, cilia also generate
water currents to carry food and
oxygen past the gills of clams
and transport food through the
digestive systems of snails.
Flagella are found primarily on
gametes, but create the water
currents necessary for
respiration and circulation in
sponges and coelenterates as
well.
http://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Hydrolasehttp://www.bio-medicine.org/biology-definition/Hydrolytic_enzyme/http://biology.about.com/library/weekly/aa041300a.htmhttp://biology.about.com/library/weekly/aa042000a.htmhttp://biology.about.com/library/weekly/aa042000a.htmhttp://en.wikipedia.org/wiki/Vacuolehttp://en.wikipedia.org/wiki/Autolysishttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Biological_membranehttp://en.wikipedia.org/wiki/Digestive_enzymehttp://en.wikipedia.org/wiki/Digestive_enzymehttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Vacuolehttp://en.wikipedia.org/wiki/Vacuolehttp://en.wikipedia.org/wiki/Vacuolehttp://en.wikipedia.org/wiki/Vacuolehttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Digestive_enzymehttp://en.wikipedia.org/wiki/Digestive_enzymehttp://en.wikipedia.org/wiki/Biological_membranehttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Autolysishttp://en.wikipedia.org/wiki/Vacuolehttp://biology.about.com/library/weekly/aa042000a.htmhttp://biology.about.com/library/weekly/aa042000a.htmhttp://biology.about.com/library/weekly/aa041300a.htmhttp://www.bio-medicine.org/biology-definition/Hydrolytic_enzyme/http://en.wikipedia.org/wiki/Hydrolasehttp://en.wikipedia.org/wiki/Organelle8/2/2019 Cell Parts and Its Functions
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ENDOPLASMIC RETICULUM The endoplasmic reticulum (ER) is
a network of flattened sacs and
branching tubules that extends
throughout the cytoplasm in plant
and animal cells. These sacs and
tubules are all interconnected by a
single continuous membrane so
that the organelle has only one
large, highly convoluted and
complexly
arranged lumen (internal space).
rough endoplasmic reticulum -
(rough ER) a vast system of
interconnected, membranous,
infolded and convoluted sacks that
are located in the cell's cytoplasm(the ER is continuous with the outer
nuclear membrane). Rough ER is
covered with ribosomes that give it
a rough appearance. Rough ER
transports materials through the
cell and produces proteins in sacks
called cisternae (which are sent to
the Golgi body, or inserted into the
cell membrane).
smooth endoplasmic reticulum -
(smooth ER) a vast system of
interconnected, membranous,infolded and convoluted tubes that
are located in the cell's cytoplasm
(the ER is continuous with the outer
nuclear membrane). The space
within the ER is called the ER lumen.
Smooth ER transports materials
through the cell. It contains
enzymes and produces and digests
lipids (fats) and membrane proteins;
smooth ER buds off from rough ER,
moving the newly-made proteins
and lipids to the Golgi body,lysosomes, and membranes.
The endoplasmic reticulum
manufactures, processes, and
transports a wide variety of
biochemical compounds for use
inside and outside of the cell.
Consequently, many of the
proteins found in the cisternal
space of the endoplasmic
reticulum lumen are there only
transiently as they pass on their
way to other locations. Other
proteins, however, are targeted
to constantly remain in the
lumen and are known as
endoplasmic reticulum resident
proteins. These special proteins,
which are necessary for theendoplasmic reticulum to carry
out its normal functions, contain
a specialized retention signal
consisting of a specific sequence
of amino acids that enables
them to be retained by the
organelle.
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ENDOSOMES AND ENDOCYTOSIS Endosomes are membrane-bound
vesicles, formed via a complex
family of processes collectively
known as endocytosis, and found
in the cytoplasm of virtually everyanimal cell. The basic mechanism
of endocytosis is the reverse of
what occurs during exocytosis or
cellular secretion.
It involves the invagination
(folding inward) of a cells
plasma membrane to surround
macromolecules or other matter
diffusing through the
extracellular fluid
MICROFILAMENTS
These filaments are primarily
structural in function and are an
important component of the
cytoskeleton. Microfilaments are
solid rods made of a protein
known as actin.
They are involved in muscle
contraction and with other types
of intracellular movements. They
help form the cells cytoskeleton,
cilia and flagella if present.
INTERMEDIATE FILAMENTS Intermediate filaments are a very
broad class of fibrous proteins
that play an important role as
both structural and functional
elements of the cytoskeleton.
Ranging in size from 8 to 12
nanometers.
Intermediate filaments function as
tension-bearing elements to help
maintain cell shape and rigidity,
and serve to anchor in place
several organelles, including the
nucleus and desmosomes.
Intermediate filaments are also
involved in formation ofthe nuclear lamina, a net-like
meshwork array that lines the
inner nuclear membrane and
governs the shape of the nucleus.
The stable cytoskeletal elements
resist mechanical forces acting on
the cell.
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MICROTUBULES
Are cylindrical structures made up
of tubulin proteins. These straight,
hollow cylinders are found
throughout the cytoplasm of all
eukaryotic cells (prokaryotes don't
have them) and carry out a variety
of functions, ranging from
transport to structural support.
Microtubules, which are about 25
nanometers in diameter, form
part of the cytoskeleton.
It gives structure and shape to a
cell, and also serve as conveyor
belts moving other organelles
throughout the cytoplasm. In
addition, microtubules are the
major components of cilia and
flagella, and participate in the
formation of spindle fibers
during cell division (mitosis).
They are involved in intracellular
and cellular movements and
form centrioles.
MITOCHONDRIA Spherical to rod-shaped organelles
with a double membrane. The
inner membrane is infolded many
times, forming a series of
projections (called cristae).
Mitochondria are generally oblong
organelles, which range in sizebetween 1 and 10 micrometers in
length, and occur in numbers that
directly correlate with the cell's
level of metabolic activity. The
word mitochondrion comes from
the Greek word mitosthread
or chondrion granule.
Mitochondria are sometimes
described as "cellular power
plants" because they generate
most of the cell's supply
ofadenosine triphosphate (ATP),
used as a source ofchemical
energy. mitochondria areinvolved in a range of other
processes, such
as signaling, cellular
differentiation, cell death, as well
as the control of the cell
cycle and cell growth
Mitochondria have been
implicated in several human
diseases, including mitochondrial
disorders and cardiac
dysfunction and may play a role
in the aging process.
http://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Cell_signalinghttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Apoptosishttp://en.wikipedia.org/wiki/Cell_cyclehttp://en.wikipedia.org/wiki/Cell_cyclehttp://en.wikipedia.org/wiki/Cell_growthhttp://en.wikipedia.org/wiki/Mitochondrial_disordershttp://en.wikipedia.org/wiki/Mitochondrial_disordershttp://en.wikipedia.org/wiki/Aging_processhttp://en.wikipedia.org/wiki/Aging_processhttp://en.wikipedia.org/wiki/Mitochondrial_disordershttp://en.wikipedia.org/wiki/Mitochondrial_disordershttp://en.wikipedia.org/wiki/Cell_growthhttp://en.wikipedia.org/wiki/Cell_cyclehttp://en.wikipedia.org/wiki/Cell_cyclehttp://en.wikipedia.org/wiki/Apoptosishttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Cell_signalinghttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Adenosine_triphosphate8/2/2019 Cell Parts and Its Functions
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NUCLEUS From Latin nucleus or nuculeus,
meaning kernel. Itis a membrane
-enclosed organelle found
in eukaryotic cells. It contains
most of the cell's genetic material,
organized as multiple longlinear DNA molecules in complex
with a large variety ofproteins,
such as histones, to
form chromosomes.
The genes within these
chromosomes are the cell's
nuclear genome.
The function of the nucleus is to
maintain the integrity of these
genes and to control the
activities of the cell by regulating
gene expression the nucleus is,
therefore, the control center ofthe cell. The main structures
making up the nucleus are
the nuclear envelope, a triple cell
membrane and membrane that
encloses the entire organelle and
unifies its contents from the
cellular cytoplasm, and
the nucleoskeleton (which
includes nuclear lamina), a
meshwork within the nucleus
that adds mechanical support,
much like the cytoskeleton,
which supports the cell as a
whole.
PEROXISOME Microbodies are a diverse group
of organelles that are found in the
cytoplasm, roughly spherical and
bound by a single membrane.
There are several types of
microbodies but peroxisomes arethe most common. Peroxisomes
are similar in appearance to
lysosomes, another type of
microbody, but the two have very
different origins.
Peroxisomes contain a variety of
enzymes, which primarily
function together to rid the cell
of toxic substances, and in
particular, hydrogen peroxide (a
common byproduct of cellularmetabolism). These organelles
contain enzymes that convert the
hydrogen peroxide to water,
rendering the potentially toxic
substance safe for release back
into the cell. Some types of
peroxisomes, such as those in
liver cells, detoxify alcohol and
other harmful compounds by
transferring hydrogen from the
poisons to molecules of oxygen(a process termed oxidation).
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PLASMA MEMBRANE
The cell membrane or plasma
membrane is a biological
membrane that separates
the interior of all cells from
the outside environment.[1]
The
cell membrane is selectively
permeable to ions and organic
molecules and controls the
movement of substances in and
out of cells. It consists of the lipid
bilayer with embedded proteins.
The membrane acts as a boundary,
holding the cell constituents
together and keeping other
substances from entering. The
plasma membrane is permeable to
specific molecules, however, and
allows nutrients and other
essential elements to enter the cell
and waste materials to leave the
cell. Small molecules, such as
oxygen, carbon dioxide, and water,
are able to pass freely across the
membrane, but the passage of
larger molecules, such as amino
acids and sugars, is carefully
regulated. Cell membranes are
involved in a variety of cellular
processes such ascell adhesion, ion
conductivity and cell signaling and
serve as the attachment surface
for several extracellular structures,
including the cell wall, glycocalyx,
and intracellular cytoskeleton.
RIBOSOMES Ribosomes are mainly found
bound to the endoplasmicreticulum and the nuclear
envelope, as well as freely
scattered throughout the
cytoplasm, depending upon
whether the cell is plant, animal,
or bacteria.
Ribosomes assemble the twenty
specific amino acid molecules toform the
particular protein molecule
determined by
the nucleotide sequence of
an RNA molecule. The organelles
serve as the protein production
machinery for the cell and are
consequently most abundant in
cells that are active in protein
synthesis, such as pancreas and
brain cells.
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NUCLEOLUS
The nucleolus (plural nucleoli) is a
non-membrane bound structure.
an organelle within the nucleus -
composed of proteins and nucleic
acids found within
the nucleus. Ribosomal
RNA (rRNA) istranscribed andassembled within the nucleolus.
It is where ribosomal RNA is
produced.
CYTOPLASM The cytoplasm is a small gel-like
substance residing between
the cell membrane holding all
the cell's internal sub-structures
(called organelles), except for the
nucleus. All the contents of the
cells ofprokaryote organisms
(which lack a cell nucleus) are
contained within the cytoplasm.
Within the cells ofeukaryote
organisms the contents of the cell
nucleus are separated from the
cytoplasm, and are then called
the nucleoplasm.
It is within the cytoplasm that
most cellular activities occur,
such as many metabolic
pathways including glycolysis,
and processes such as cell
division.
VACUOLE Fluid-filled, membrane-surrounded
cavities inside a cell. Vacuoles are
essentially enclosed compartments
which are filled with water
containing inorganic and organic
molecules including
enzymes in solution, though in
certain cases they may contain
solids which have been engulfed.
Vacuoles are formed by the fusion
of multiple membrane vesicles and
are effectively just larger forms of
these.
The vacuole fills with food being
digested and waste material that
is on its way out of the cell.
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NUCLEAR PORE
NUCLEAR ENVELOPE
Nuclear pores are
large protein complexes that cross
the nuclear envelope, which is the
double membrane surrounding
the eukaryotic cell nucleus. There
are about on average 2000
nuclear pore complexes in the
nuclear envelope of a vertebrate
cell, but it varies depending on cell
type and the stage in the life cycle.
The proteins that make up the
nuclear pore complex are known
as nucleoporins.
A nuclear envelope (NE) (also
known as the perinuclear
envelope, nuclear
membrane, nucleolemma or karyo
theca). Is a double-membrane
structure that is pierced by thepores.
Nuclear pore complexes allow
the transport of water-soluble
molecules across the nuclear
envelope. This transport
includes RNA and ribosomes
moving from nucleus to the
cytoplasm and proteins (such
as DNA
polymerase and lamins), carbohy
drates, signal
molecules and lipids moving into
the nucleus. It is notable that
the nuclear pore complex(NPC)
can actively conduct 1000
translocations per complex per
second.
Is a double lipid bilayer that
encloses the genetic material
ineukaryotic cells. The nuclear
envelope also serves as the
physical barrier, separating the
contents of the nucleus (DNA in
particular) from
the cytosol (cytoplasm).Many nuclear pores are inserted
in the nuclear envelope, which
facilitate and regulate the
exchange of materials
(proteins such as transcription
factors, and RNA) between the
nucleus and the cytoplasm.
http://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Nuclear_envelopehttp://en.wikipedia.org/wiki/Endomembrane_systemhttp://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Cell_nucleushttp://en.wikipedia.org/wiki/Nuclear_envelopehttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Ribosomeshttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/DNA_polymerasehttp://en.wikipedia.org/wiki/DNA_polymerasehttp://en.wikipedia.org/wiki/Laminhttp://en.wikipedia.org/wiki/Carbohydrateshttp://en.wikipedia.org/wiki/Carbohydrateshttp://en.wikipedia.org/wiki/Signaling_moleculehttp://en.wikipedia.org/wiki/Signaling_moleculehttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Lipid_bilayerhttp://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Cell_nucleushttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Cytoplasmhttp://en.wikipedia.org/wiki/Nuclear_porehttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Nuclear_porehttp://en.wikipedia.org/wiki/Cytoplasmhttp://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Cell_nucleushttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Lipid_bilayerhttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Signaling_moleculehttp://en.wikipedia.org/wiki/Signaling_moleculehttp://en.wikipedia.org/wiki/Carbohydrateshttp://en.wikipedia.org/wiki/Carbohydrateshttp://en.wikipedia.org/wiki/Laminhttp://en.wikipedia.org/wiki/DNA_polymerasehttp://en.wikipedia.org/wiki/DNA_polymerasehttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Ribosomeshttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Nuclear_envelopehttp://en.wikipedia.org/wiki/Cell_nucleushttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Endomembrane_systemhttp://en.wikipedia.org/wiki/Nuclear_envelopehttp://en.wikipedia.org/wiki/Protein8/2/2019 Cell Parts and Its Functions
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PLANT CELL
Plant cells like animal cells are eukaryotic, i.e. they contain membrane bound nuclei and cell
organelles. A plant cell differs from an animal cell in having certain distinctive structures - cell wall,
vacuoles, plasmodesmata and plastids. On the contrary, plant cells lack centrioles and intermediate
filaments, which are present in animal cells. Despite these, plant and animal cells share several
similarities in structure, parts and their roles.
Plant cells are classified into three types, based on the structure and function, viz. parenchyma,
collenchyma and sclerenchyma. The parenchyma cells are living, thin-walled and undergo repeated cell
division for growth of the plant. They are mostly present in the leaf epidermis, stem pith, root and fruit
pulp. Mature collenchyma cells are living, and provide stretchable support to the plant. Lastly,
sclerenchyma cells (e.g. fiber cells) are hard, non-living and give mechanical support to plants. Now, let
us see the different parts of a plant cell with their significant roles.
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CELL PARTS AND ITS FUNCTIONS
CELL WALL DESCRIPTION FUNCTION
The cell wall is the tough,
usually flexible but sometimes
fairly rigid layer that surrounds
some types ofcells. It is located
outside the cell membrane. It
comprises cellulose,
hemicellulose, pectin and at
other times, lignin. As expected,
it remains connected with the
cell walls of other cells.
The prime functions of cell wall
are protection, giving structural
support and helping in the filter
mechanism. A major function of
the cell wall is to act as a pressure
vessel, preventing over-expansion
when water enters the cell
CELL MEMBRANE Cell membrane, also called
plasma membrane, is present
inside the cell wall and
surrounds the cytoplasm. the
thin layer of protein and fat that
surrounds the cell, but is inside
the cell wall. The cell membrane
is semipermeable, allowing
some substances to pass into
the cell and blocking others.
It connects the intracellular
components (organelles and
cytoplasm) with the extracellular
environment, and helps in
protection and transportation.
The cell membrane is permeable
to specific substances only.
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NUCLEAR MEMBRANE The nuclear membrane and the
nuclear envelope mean one and
same thing. As the name reveals,
it is the outer covering of the
nucleus.
It separates the cytoplasmic
contents from the nuclear
contents. Nonetheless, minute
pores (nuclear pores) are present
for exchanging materials between
the nucleus and cytoplasm.
NUCLEUSNucleus is a specialized organelle,
which contains the plant's
hereditary material i.e. DNA
(Deoxyribonucleic Acid). Inside
the nucleus, a dense, spherical
body called nucleolus is present.
The nucleus contains structures,
which regulates the cell cycle,
growth, protein synthesis and
reproductive function.
The function of the nucleus is to
maintain the integrity of these
genes and to control the activities
of the cell by regulating gene
expression the nucleus is,
therefore, the control center of
the cell. The nucleus controls
many of the functions of the cell
(by controlling protein synthesis)
and contains DNA (in
chromosomes).
VACUOLEA large, membrane-bound space
within a plant cell that is filled
with fluid. Most plant cells have a
single vacuole that takes up much
of the cell.
They function as storage,
excretory and secretory
organelles. The membrane
surrounding a vacuole is called
tonoplast. A mature plant cell has
a single vacuole at the near
center of the cell (central
vacuole), which contributes toabout 30-80 percent of the cell's
volume.
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CYTOPLASM Cytoplasm is filled up by cytosol,
which is a gelatinous and
semitransparent fluid. All
the organelles of the plant
cell are present in this cytoplasm.
This part of the plant cell is the
site for cell division, glycolysis and
many other cellular activities.
Also, the cytoskeleton elements
(microtubules and
microfilaments) are present in the
cytosol.
PLASTID/CHLOROPLASTSChloroplasts are organelles found
in plant cells and
other eukaryotic organisms that
conduct photosynthesis.
Chloroplasts are green because
they contain
the pigment chlorophyll. The
word chloroplastis derived from
the Greek words chloros which
means green, andplastis which
means "the one who forms".
Chloroplasts are members of a
class of organelles known
as plastids.
Plastids are organelles
responsible for photosynthetic
activity, manufacturing and
storage of chemical compounds in
plants. Chloroplast is an
important form of plastid
containing chlorophyll pigment,
which helps in harvesting light
energy and converting it to
chemical energy. Likewise,
chromoplast and other plastids
are present in a plant cell.
MITOCHONDRIAMitochondrion is a membrane-
enclosed organellefound in
most eukaryotic cells.[1]
These
organelles range from 0.5 to
1.0 micrometers (m) in
diameter. Mitochondria are
sometimes described as "cellular
power plants" because they
generate most of the cell's supply
ofadenosine triphosphate (ATP),
used as a source ofchemical
energy.
They are responsible for breaking
down complex carbohydrate and
sugar molecules to simpler forms,
which the plants can use. Other
than this, mitochondria are
crucial for cell signaling, cycle,
division, growth and death.
http://www.buzzle.com/articles/plant-cell-organelles.htmlhttp://www.buzzle.com/articles/plant-cell-organelles.htmlhttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Plant_cellhttp://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Photosynthesishttp://en.wikipedia.org/wiki/Pigmenthttp://en.wikipedia.org/wiki/Chlorophyllhttp://en.wikipedia.org/wiki/Plastidhttp://en.wikipedia.org/wiki/Biological_membranehttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Mitochondria#cite_note-mitosomes-0http://en.wikipedia.org/wiki/Mitochondria#cite_note-mitosomes-0http://en.wikipedia.org/wiki/Mitochondria#cite_note-mitosomes-0http://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Chemical_energyhttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/Mitochondria#cite_note-mitosomes-0http://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Biological_membranehttp://en.wikipedia.org/wiki/Plastidhttp://en.wikipedia.org/wiki/Chlorophyllhttp://en.wikipedia.org/wiki/Pigmenthttp://en.wikipedia.org/wiki/Photosynthesishttp://en.wikipedia.org/wiki/Eukaryotehttp://en.wikipedia.org/wiki/Plant_cellhttp://en.wikipedia.org/wiki/Organellehttp://www.buzzle.com/articles/plant-cell-organelles.htmlhttp://www.buzzle.com/articles/plant-cell-organelles.html8/2/2019 Cell Parts and Its Functions
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ENDOPLASMIC RETICULUMRough endoplasmic reticulum -
(rough ER) a vast system of
interconnected, membranous,
infolded and convoluted sacks
that are located in the cell's
cytoplasm. Rough ER is covered
with ribosomes that give it a
rough appearance.
Smooth endoplasmic reticulum -
(smooth ER) a vast system of
interconnected, membranous,
infolded and convoluted tubes
that are located in the cell's. The
space within the ER is called the
ER lumen.
The endoplasmic reticulum (ER)
organelle plays a major role in
manufacturing and storage of
chemical compounds, like
glycogen and steroids. It is alsoinvolved in translation and
transportation of protein. ER is
also connected to the nuclear
membrane, so as to make a
channel between the cytoplasm
and the nucleus.
PLASMODESMATA Plasmodesmata are microscopic
channels which traverse the cell
walls of plant cells. They are
formed when portions of
the endoplasmic reticulum are
trapped across the middle
lamella as new cell wall is laid
down between two newly divided
plant cells and these eventuallybecome the cytoplasmic
connections between cells
(primary plasmodesmata).
Plasmodesma (plural
plasmodesmata) is a small
opening, which connects plant
cells with each other. Present
only in some types of algal cells
and plants cells, this connecting
channel enables transport of
materials and allows
communication between the
cells. In a single plant cell, about1,000-100,000 plasmodesmata
are present.
GOLGI APPARATUS Also called the golgi apparatus or
golgi complex. A flattened,
layered, sac-like organelle that
looks like a stack of pancakes andis located near the nucleus.
It is an organelle responsible for
processing of macromolecules
(like carbohydrates, proteins and
fats) and packaging them intomembrane-bound vesicles for
transportation purposes. Golgi
bodies are present near to the
nucleus of the plant cell.
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RIBOSOMESTiny spherical bodies that help
make proteins. Found in the
cytoplasm or attached to the
endo plasmic reticulum.
Ribosomes are organelles, which
are made up of 60% RNA
(Ribonucleic Acid) and 40%
protein, and play an important
role in protein translation. It
won't be wrong to say that the
main site of protein synthesis is
ribosome.
The organelles serve as the
protein production machinery for
the cell and are consequently
most abundant in cells that are
active in protein synthesis, such as
pancreas and brain cells.
MICROBODIESMicrobodies are single,
membrane-bound, globular
shaped organelles, which are
found in the cytoplasm. They
range in size from 0.5-1
micrometer, and contain
degradative enzymes. Many kinds
of microbodies are present in a
plant cell, of which the two most
common types are peroxisomes
and glyoxysomes.
Microbodies are specialized as
containers for metabolic activity.
MICROTUBULESMicrotubules are straight, hollow,
tubular cylinders, which are major
elements of the cytoskeleton.
These rope-like polymers
oftubulin can grow as long as 25
micrometers and are highly
dynamic. The outer diameter of
microtubule is about 25nm.
These plant cell structures are
involved in synthesizing cell wall.
Function wise, they are crucial for
structural support, cell division
and transport of vesicles.
Microtubules in a plant cell are
simpler, as compared to those of
an animal cell. They are conveyer
belts inside the cells. They move
vesicles, granules, organelles like
mitochondria, and chromosomes
via special attachment proteins.
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MICROFILAMENTS Microfilaments are thin, filament
like structures found in the
cytosol, which contain actin
subunits. These along with the
microtubules make up the
cytoskeleton of plants cells.
These linear polymers ofactin
subunits are flexible and relatively
strong, resisting buckling by
multi-piconewton compressive
forces and filament fracture by
nanonewton tensile forces.
Microfilaments are highly
versatile, functioning in cell
crawling, amoeboid movement,
and changes in cell shape.
The cell membrane
The cell membrane, also
called the plasma
membrane or
plasmalemma, is a
semipermeable lipid
bilayer common to all
living cells. It contains a
variety of biological
molecules, primarily
proteins and lipids, which
are involved in a vast
array of cellular
processes. It also servesas the attachment point
for both the intracellular
cytoskeleton and, if
present, the cell wall.
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Parts and its functions:
1. Glycoproteins- are proteins that contain oligosaccharide chains (glycans) covalently
attached to polypeptide side-chains. The carbohydrate is attached to the protein ina cotranslational or posttranslational modification. Glycoproteins are often
important integral membrane proteins, where they play a role in cellcell interactions.
Glycoproteins also occur in the cytosol, but their functions and the pathways producing
these modifications in this compartment are less well-understood.
2. Glycolipids- are lipids with a carbohydrate attached. Their role is to provide energy and also
serve as markers for cellular recognition.
3. Globular protein-or spheroproteins are one of the two main protein classes,
comprising "globe"-like proteins that are more or less soluble in aqueous solutions (where
they form colloidal solutions). This characteristic distinguishes them from fibrous
proteins (the other class), which are practically insoluble.
The term globin can refer more specifically to proteins including the globin fold.
4. Phospholipids- are a class oflipids that are a major component of all cell membranes as
they can form lipid bilayers. The first phospholipid identified as such in biological tissues
was lecithin, or phosphatidylcholine. The structure of the phospholipid molecule generally
consists of hydrophobic tails and a hydrophilic head. It is usually found
with cholesterol molecules which are found in-between the spaces of the phospholipid..
5. Proteins within the membrane are key to the functioning of the overall membrane. These
proteins mainly transport chemicals and information across the membrane. Every
membrane has a varying degree of protein content. Proteins can be in the form of
peripheral or integral.
Type Description Examples
Integral proteins
or transmembrane proteins
Span the membrane and have a
hydrophilic cytosolic domain, which interacts with
internal molecules, a hydrophobic membrane-spanning domain that anchors it within the cell
membrane, and a hydrophilic extracellular domain
that interacts with external molecules. The
hydrophobic domain consists of one, multiple, or a
combination of-helices and
sheet protein motifs.
Ion channels,proton
pumps, G protein-
coupled receptor
http://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Oligosaccharidehttp://en.wikipedia.org/wiki/Glycanshttp://en.wikipedia.org/wiki/Peptidehttp://en.wikipedia.org/wiki/Translation_(genetics)http://en.wikipedia.org/wiki/Posttranslational_modificationhttp://en.wikipedia.org/wiki/Integral_membrane_proteinshttp://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Carbohydratehttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Genetic_markerhttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Spherehttp://en.wikipedia.org/wiki/Aqueous_solutionhttp://en.wikipedia.org/wiki/Colloidalhttp://en.wikipedia.org/wiki/Fibrous_proteinhttp://en.wikipedia.org/wiki/Fibrous_proteinhttp://en.wikipedia.org/wiki/Globinhttp://en.wikipedia.org/wiki/Globin_foldhttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Lipid_bilayerhttp://en.wikipedia.org/wiki/Lecithinhttp://en.wikipedia.org/wiki/Phosphatidylcholinehttp://en.wikipedia.org/wiki/Cholesterolhttp://en.wikipedia.org/wiki/Integral_proteinhttp://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Protein_domainshttp://en.wikipedia.org/wiki/Alpha_helixhttp://en.wikipedia.org/wiki/Alpha_helixhttp://en.wikipedia.org/wiki/Alpha_helixhttp://en.wikipedia.org/wiki/Beta_sheethttp://en.wikipedia.org/wiki/Beta_sheethttp://en.wikipedia.org/wiki/Beta_sheethttp://en.wikipedia.org/wiki/Structural_motifhttp://en.wikipedia.org/wiki/Proton_pumphttp://en.wikipedia.org/wiki/Proton_pumphttp://en.wikipedia.org/wiki/G_protein-coupled_receptorhttp://en.wikipedia.org/wiki/G_protein-coupled_receptorhttp://en.wikipedia.org/wiki/G_protein-coupled_receptorhttp://en.wikipedia.org/wiki/G_protein-coupled_receptorhttp://en.wikipedia.org/wiki/Proton_pumphttp://en.wikipedia.org/wiki/Proton_pumphttp://en.wikipedia.org/wiki/Structural_motifhttp://en.wikipedia.org/wiki/Beta_sheethttp://en.wikipedia.org/wiki/Beta_sheethttp://en.wikipedia.org/wiki/Alpha_helixhttp://en.wikipedia.org/wiki/Protein_domainshttp://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Integral_proteinhttp://en.wikipedia.org/wiki/Cholesterolhttp://en.wikipedia.org/wiki/Phosphatidylcholinehttp://en.wikipedia.org/wiki/Lecithinhttp://en.wikipedia.org/wiki/Lipid_bilayerhttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Globin_foldhttp://en.wikipedia.org/wiki/Globinhttp://en.wikipedia.org/wiki/Fibrous_proteinhttp://en.wikipedia.org/wiki/Fibrous_proteinhttp://en.wikipedia.org/wiki/Colloidalhttp://en.wikipedia.org/wiki/Aqueous_solutionhttp://en.wikipedia.org/wiki/Spherehttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Genetic_markerhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Carbohydratehttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Integral_membrane_proteinshttp://en.wikipedia.org/wiki/Posttranslational_modificationhttp://en.wikipedia.org/wiki/Translation_(genetics)http://en.wikipedia.org/wiki/Peptidehttp://en.wikipedia.org/wiki/Glycanshttp://en.wikipedia.org/wiki/Oligosaccharidehttp://en.wikipedia.org/wiki/Protein8/2/2019 Cell Parts and Its Functions
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Lipid anchored proteins
Covalently bound to single or multiple lipid
molecules; hydrophobically insert into the cell
membrane and anchor the protein. The protein
itself is not in contact with the membrane.
G proteins
Peripheral proteins Attached to integral membrane proteins, or
associated with peripheral regions of the lipid
bilayer. These proteins tend to have only
temporary interactions with biological membranes,
and, once reacted the molecule, dissociates to
carry on its work in the cytoplasm.
Some enzymes,some
hormones
EUKARYOTIC AND PROKARYOTIC CELL
EUKARYOTICEu =true, karyon =nucleus
PROKARYOTICPro =before, karyon =nucleus
SIMILARITIES Both have DNA as their genetic material (its DNA thattells cells what kind of cells they should be).
Both are covered by a cell membrane.
Both contain RNA.
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Both are made from the same basic chemicals:
carbohydrates, proteins, nucleic acid, minerals, fats and
vitamins.
Both have ribosomes (the structures on which proteins
are made).
Both regulate the flow of the nutrients and wastes that
enter and leave them.
Both have similar basic metabolism (life processes) like
photosynthesis and reproduction.
Both require a supply of energy.
Both are highly regulated by elaborate sensing systems
("chemical noses) that make them aware of the reactionswithin them and the environment around them.
DIFFERENCES
Eukaryotic cells have a true
nucleus, bound by a double
membrane.
Eukaryotic DNA is linear
Eukaryotic DNA is complexed with
proteins called "histones," and is
organized into chromosomes
Prokaryotic cells have no
nucleus.
(Prokaryotic cell has no
nucleus because its much
smaller size means that all
materials within the cell are
relatively close together.)
Prokaryotic DNA is circular (it
has no ends).
Prokaryotic DNA is "naked,"meaning that it has no
histones associated with it,
and it is not formed into
chromosomes.
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The ribosomes of the eukaryotic
cells are larger and more complex.
The cytoplasm of eukaryotic cells
is filled with a large, complex
collection of organelles, many of
them enclosed in their own
membranes.
Eukaryotic cells are often
multicellular.
Eukaryotic cells reproduce/divide
by mitosis/meiosis
Larger cells (>10 m)
Always has a cytoskeleton
Reproduction is asexual or sexual
Common metabolic pathways
The ribosomes of prokaryotic
cells are small and clear.
The prokaryotic cell contains
no membrane-bound
organelles which are
independent of the plasma
membrane.
Prokaryotic cells are always
unicellular
Prokaryotic cells
reproduce/divide by binary
fission
Small cells (
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Biological function of a cell
1. Movement or Motility- is a biological term which refers to the ability to move spontaneously
and actively, consuming energy in the process. All animals are motile but the term applies to
single-celled and simple multicellular organisms, as well as to some mechanisms of fluid flow in
multicellular organs, in addition to animal locomotion. Motile marine animals are commonly
called free-swimming.
* Cell motility is one of the crowning achievements of evolution. Primitive cells were probably
immobile, carried by currents in the primordial milieu. With the evolution of multicellular
organisms, primitive organs were formed by migrations of single cells and groups of cells from
distant parts of the embryo. In adult organisms, movements of single cells in search of foreign
organisms are integral to the hosts defenses against infection; on the other hand, uncontrolled
cell migration is an ominous sign of a cancerous cell.
2. Sensitivity or Irritability- The ability of the cell to receive and respond to a stimulus. Muscle cells
are irritable and respond to stimuli. Muscle twitch is defined as contraction and relaxation in the
muscle cell. The stimulus needs to be above a certain threshold for the muscle fibres to react.
The more the stimulus, the greater the strength of the contraction.
3. Growth and metabolism- Between successive cell divisions, cells grow through the functioning
of cellular metabolism. Cell metabolism is the process by which individual cells process nutrient
molecules. Metabolism has two distinct divisions: catabolism, in which the cell breaks down
complex molecules to produce energy and reducing power, and anabolism, in which the cell
uses energy and reducing power to construct complex molecules and perform other biological
functions. Complex sugars consumed by the organism can be broken down into a less chemically
complex sugar molecule called glucose. Once inside the cell, glucose is broken down to make
adenosine triphosphate (ATP), a form of energy, through two different pathways.
*The first pathway, glycolysis, requires no oxygen and is referred to as anaerobic metabolism.
Each reaction is designed to produce some hydrogen ions that can then be used to make energy
packets (ATP). In prokaryotes, glycolysis is the only method used for converting energy.
*The second pathway, called the Krebs cycle, or citric acid cycle, occurs inside the mitochondria
and can generate enough ATP to run all the cell functions.
4. Mutations- are changes in a genomic sequence: the DNA sequence of a cell's genome or the
DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in
the cell. Mutations are caused by radiation, viruses, transposons and mutagenic chemicals, as
well as errors that occur during meiosis or DNA replication. They can also be induced by the
http://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Animalhttp://en.wikipedia.org/wiki/Animal_locomotionhttp://en.wikipedia.org/wiki/Marine_animalhttp://www.biology-online.org/dictionary/Cellhttp://www.biology-online.org/dictionary/Stimulushttp://en.wikipedia.org/wiki/Catabolismhttp://en.wikipedia.org/wiki/Anabolismhttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Glycolysishttp://en.wikipedia.org/wiki/Fermentation_(biochemistry)http://en.wikipedia.org/wiki/Citric_acid_cyclehttp://en.wikipedia.org/wiki/Genomehttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Genomehttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Radioactive_decayhttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Transposonhttp://en.wikipedia.org/wiki/Mutagenhttp://en.wikipedia.org/wiki/DNA_errorhttp://en.wikipedia.org/wiki/Meiosishttp://en.wikipedia.org/wiki/DNA_replicationhttp://en.wikipedia.org/wiki/DNA_replicationhttp://en.wikipedia.org/wiki/Meiosishttp://en.wikipedia.org/wiki/DNA_errorhttp://en.wikipedia.org/wiki/Mutagenhttp://en.wikipedia.org/wiki/Transposonhttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Radioactive_decayhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Genomehttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Genomehttp://en.wikipedia.org/wiki/Citric_acid_cyclehttp://en.wikipedia.org/wiki/Fermentation_(biochemistry)http://en.wikipedia.org/wiki/Glycolysishttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Anabolismhttp://en.wikipedia.org/wiki/Catabolismhttp://www.biology-online.org/dictionary/Stimulushttp://www.biology-online.org/dictionary/Cellhttp://en.wikipedia.org/wiki/Marine_animalhttp://en.wikipedia.org/wiki/Animal_locomotionhttp://en.wikipedia.org/wiki/Animalhttp://en.wikipedia.org/wiki/Biology8/2/2019 Cell Parts and Its Functions
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organism itself, by cellular processes such as hypermutation. A mutation is passed to the
offspring stably, unless it is a dynamic mutation.
5. Respiration-is the set of the metabolic reactions and processes that take place in
the cells oforganisms to convert biochemical energy from nutrients into adenosinetriphosphate (ATP), and then release waste products. The reactions involved in respiration
are catabolic reactions that involve the redox reaction (oxidation of one molecule and
the reduction of another). Respiration is one of the key ways a cell gains useful energy to fuel
cellular reformations.
6. Excretion- is the process in which a cell gets rid of the wastes and toxins that could be damaging
it, by its cell membrane. In single-celled organisms, waste products are discharged directly
through the surface of the cell. Multicellular organisms utilize more complex excretory methods.
Higher plants eliminate gases through the stomata, or pores, on the surface of leaves. Animals
have special excretory organs.
7. Secretion- Many cells secrete proteins into their surrounding extracellular fluid. Some cells, for
example, secrete regulatory molecules such as hormones and neurotransmitters. Others release
digestive enzymes, antibodies, or mucus. And throughout the body, cells such
as fibroblasts secrete collagen and other structural proteins to provide strength and hold the
body together.
8. Absorption- is the uptake of materials from a cells' external environment. The process ofabsorbing or assimilating substances into cells or across the tissues and organs through
diffusion or osmosis, as in absorption of nutrients by the digestive system, or absorption of
drugs into the bloodstream.
9. Energy- Life is an energy intensive process. It takes energy to operate muscles, extract wastes,
make new cells, heal wounds, even to think. Its in an organisms cells where all this energy is
spent. In some cells, as much as half of a cells energy output is used to transfer molecules
across the cell membrane, a process called active transport. Cell movements require energy and
thousands of energy-hungry chemical reactions go on in every living cell, every second, every
day. The kind of energy cells use is chemical bond energy, the shared electrons that holds atoms
together in molecules.
10. Transport- Some cells are responsible for transporting materials from one place in the body to
another. In humans, for instance, cells lining the small intestine transport the molecular
products of digestion from the inside of the gut to the bloodstream. Glucose, for instance, which
http://en.wikipedia.org/wiki/Cellular_processeshttp://en.wikipedia.org/wiki/Somatic_hypermutationhttp://en.wikipedia.org/wiki/Dynamic_mutationhttp://en.wikipedia.org/wiki/Metabolismhttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Organismhttp://en.wikipedia.org/wiki/Energy#Energy_and_lifehttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Catabolismhttp://en.wikipedia.org/wiki/Redoxhttp://en.wikipedia.org/wiki/Redoxhttp://en.wikipedia.org/wiki/Redoxhttp://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Multicellular_organismhttp://en.wikipedia.org/wiki/Planthttp://en.wikipedia.org/wiki/Stomatahttp://www.biology-online.org/dictionary/Cellshttp://www.biology-online.org/dictionary/Diffusionhttp://www.biology-online.org/dictionary/Osmosishttp://www.biology-online.org/dictionary/Osmosishttp://www.biology-online.org/dictionary/Diffusionhttp://www.biology-online.org/dictionary/Cellshttp://en.wikipedia.org/wiki/Stomatahttp://en.wikipedia.org/wiki/Planthttp://en.wikipedia.org/wiki/Multicellular_organismhttp://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Redoxhttp://en.wikipedia.org/wiki/Redoxhttp://en.wikipedia.org/wiki/Redoxhttp://en.wikipedia.org/wiki/Catabolismhttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Adenosine_triphosphatehttp://en.wikipedia.org/wiki/Energy#Energy_and_lifehttp://en.wikipedia.org/wiki/Organismhttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Metabolismhttp://en.wikipedia.org/wiki/Dynamic_mutationhttp://en.wikipedia.org/wiki/Somatic_hypermutationhttp://en.wikipedia.org/wiki/Cellular_processes8/2/2019 Cell Parts and Its Functions
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is also called blood sugar, is transported by specialized cells that move glucose molecules out of
the intestine together with sodium ions
11. Storage- Some cells specialize in storage. Adipose cells, for instance, serve the purpose of
storing large quantities of triacylglyceride, or fat, explain Drs. Campbell and Farrell. While mostbody cells can burn sugar, protein or fat for energy, fat provides far more energy per gram of
weight, so its most efficient as a stored fuel. While adipose cells dont engage in many other
functionstheyre not particularly active with regard to anything else the body doesthey do
serve the valuable role of providing for the rest of the bodys energy needs when food is scarce.
12. Communication- In order to keep a multicellular organism running efficiently, there must be
cell-to-cell communication. While neighboring cells can communicate with one another without
significant difficulty, things become a bit more complicated when, for instance, a gland in the
brain needs to send a message to the gonads. Specialized cells, therefore, secrete
communication molecules, called hormones, into the blood stream. The anterior pituitary gland
in the brain, for instance, secretes a hormone that travels throughout the body, but only cells on
the gonads respond to the hormone, notes Lauralee Sherwood in her text Human Physiology.
In women, the gonadsovaries, in this caseripen an egg in preparation for ovulation in
response to the pituitary hormone. In men, the testes produce sperm. Neurons are also
communication cells. Instead of sending chemical messages via the bloodstream, however, they
communicate directly with one another and with neighboring cells by using electrical impulses.
13. Reproduction- organisms must produce new off-springs to replace the dying ones in the
population. This is one of the most important life process. A species has to carry forward itsprogeny or else it would become extinct.
Refences:
www.wikipedia.org (accesed November, 2011)
http://www.cod.edu/people/faculty/fancher/prokeuk.htm
http://www.biologymad.com/resources/AS%20
Cells.pdf
http://www.enchantedlearning.com/subjects/animals/cell/
http://jgimp.tripod.com/cells.html
http://www.wikipedia.org/http://www.cod.edu/people/faculty/fancher/prokeuk.htmhttp://www.cod.edu/people/faculty/fancher/prokeuk.htmhttp://www.biologymad.com/resources/AS%20Cells.pdfhttp://www.biologymad.com/resources/AS%20Cells.pdfhttp://www.enchantedlearning.com/subjects/animals/cell/http://www.enchantedlearning.com/subjects/animals/cell/http://jgimp.tripod.com/cells.htmlhttp://jgimp.tripod.com/cells.htmlhttp://www.enchantedlearning.com/subjects/animals/cell/http://www.enchantedlearning.com/subjects/animals/cell/http://www.biologymad.com/resources/AS%20Cells.pdfhttp://www.biologymad.com/resources/AS%20Cells.pdfhttp://www.cod.edu/people/faculty/fancher/prokeuk.htmhttp://www.cod.edu/people/faculty/fancher/prokeuk.htmhttp://www.wikipedia.org/8/2/2019 Cell Parts and Its Functions
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Bicol University
COLLEGE OF SCIENCE
Chemistry Department
Legazpi city
ACTIVITY no. 1
Inna Coleen A. Yanzon
BS NURSING- 1B