CYTOPLASM
What is Cytoplasm and
How Does it Work
What is Cytoplasm
• Cytoplasm is defined as the material that lies within
the cytoplasmic membrane, or the membrane that
surrounds a cell. It contains none of a cell's genetic
material, because this is contained in the nucleus. It
does, however, contain a lot of water, and the other
organelles of the cells. It provides a platform upon
which they can operate within the cell. It is made up of
proteins, vitamins, ions, nucleic acids, amino acids,
sugars, carbohydrates and fatty acids. All of the
functions for cell expansion, growth and replication are
carried out in the cytoplasm of a cell.
Functions of Cytoplasm
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Cytoplasm has three basic functions within the cells of living organisms. Made of three basic
components, cytoplasm is a medium of suspension for the organelles in the cell. The function of
cytoplasm is also a means of transport for genetic material and the products of cellular respiration.
As cytoplasm is a fluid, it acts as a buffer, protecting the cell's genetic material and organelles from
damage due to movement or collision with other cells.
The three main parts of cytoplasm are cytosol, the organelles and cytoplasmic inclusions. Cytosol is
the liquid that suspends the organelles; it is mainly water with some protein strands that help
support the organelles. Organelles are specialized parts of the cell, each having its own function;
major functions of the organelles include cellular respiration, creation of new proteins and
destruction of waste material. Finally, cytoplasmic inclusions are non-soluble molecules floating
within the cytoplasm; in many cells, these inclusions are stored fats and sugars ready for cellular
respiration.
Cytoplasm's primary function is to act as a medium of suspension for a cell's organelles, keeping a
cell's inner structure intact. As organelles are not neutrally buoyant in cytoplasm due to the
changing concentrations of solutes, the protein strands described in the previous paragraph are
necessary to keep organelles in place. The cytoplasm and proteins prevent gravity from grouping
the organelles near the bottom of the cell, an event that would greatly impede their function.
Image of Cytoplasm
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Cytoplasm is the fluid that fills a cell. Scientists used to call the fluid protoplasm. Early on, they didn't know about
the many different types of fluids in the cell. There is special fluid in the mitochondria, endoplasmic reticulum,
Golgi apparatus, and nucleus. The only two 'plasms' left are cytoplasm (the fluid in the cell also called cytosol) and
nucleoplasm (the fluid in the nucleus). Each of those fluids has a very different composition.
The cell organelles are suspended in the cytosol. You will learn that the microfilaments and microtubules set up a
"skeleton" of the cell and the cytosol fills the spaces. The cytoplasm has many different molecules dissolved in
solution. You'll find enzymes, fatty acids, sugars, and amino acids that are used to keep the cell working. Waste
products are also dissolved before they are taken in by vacuoles or sent out of the cell.
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Special Fluids in the Nucleus
Nucleoplasm has a little different composition. Nucleoplasm can only be found inside of the nucleus. It doesn't
have big organelles in suspension. The nucleoplasm is the suspension fluid that holds the cell's chromatin and
nucleolus. It is not always present in the nucleus. When the cell divides, the nuclear membrane dissolves and the
nucleoplasm is released. After the cell nucleus has reformed, the nucleoplasm fills the space again.
More than Filling
The cytosol in a cell does more than just suspend the organelles. It uses its dissolved enzymes to break down all of
those larger molecules. The products can then be used by the organelles of the cell. Glucose may exist in the
cytosol but the mitochondria can't use it for fuel. The cytosol has enzymes that break glucose down into pyruvate
molecules that are then sent to the mitochondria.
Composition of Cytoplasm
• About 80% of the cytoplasm is H2O. During
interphase the extra base pairs needed for
DNA replication are found here. Sugar and
phosphate are dissolved in the cytoplasm.
Other substances include amino acids, nucleic
acids, enzymes, carbohydrates, lipids, nonorganic ions, and very light molecular
compounds. The liquid of the cytoplasm is
called the cytosol.
• Have you ever wondered what fills up your cells? Look no further... it's
cytoplasm, a gooey, liquid substance that holds everything in a cell outside
of the nucleus.
• Every cell has three parts, whether it be a blood cell, brain cell, or
reproductive cell. It contains a membrane with channels to let materials
into and out of a cell. It contains cytoplasm, which can be basically defined
as anything in between the membrane and the nucleus of a cell. And it
contains the nucleus, which is the home of a cell's chromosomes, or
genetic material.
• Cytoplasm is defined as the material that lies within the cytoplasmic
membrane, or the membrane that surrounds a cell. It contains none of a
cell's genetic material, because this is contained in the nucleus. It does,
however, contain a lot of water, and the other organelles of the cells. It
provides a platform upon which they can operate within the cell. It is
made up of proteins, vitamins, ions, nucleic acids, amino acids, sugars,
carbohydrates and fatty acids. All of the functions for cell expansion,
growth and replication are carried out in the cytoplasm of a cell.
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The organelles inside cytoplasm are very important for the maintenance of the cell. Some of the
most important organelles that cytoplasm contains are the mitochondria, proteins, ribosomes, the
endoplasmic reticulum, the Golgi apparatus, lysosomes and the cytoskeleton. Mitochondria are
sites of energy-making, because they contain the materials necessary for ATP synthesis, or the
fueling of the cell. The cytoskeleton is a network of protein fibers that give support to the cell, and
help it maintain shape. The endoplasmic reticulum is the site of lipid (fat) and protein synthesis,
and the Golgi apparatus is the packaging plant of a cell. Lysosomes are small sacs of digestive
enzymes in the cell for eating. They are like little stomachs traveling around the cell! Proteins and
ribosomes move through the cell acting as catalysts for various chemical processes.
In a roundabout way, some genetic material does reach the cytoplasm. The endoplasmic reticulum
is an RNA-coding area, before this information is sent to the nucleus.
If a person is born with irregular cytoplasm, in most cases they do not live. Cytoplasm is so essential
to the cell, it requires working order to operate and maintain life. However, some unusual cases of
cytoplasmic irregularity do exist, and scientists are learning how to transplant cytoplasm into cells
to help them function normally. Also, cytoplasm in animals is being examined for ways to enter the
cell and penetrate nucleii with cures for certain diseases.
Other uses for cytoplasm are being developed. Recently, it allowed scientists a close view of the HIV
virus as it entered a cell. Cytoplasm also is used extensively in cloning, when information is
transferred from the mother to the cloning host. If the cytoplasm of a reproductive egg is faulty,
now new cytoplasm can be transferred into the egg to maintain reproductive power. Plant
cytoplasm is used for new biotechnology experiments every day.
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Cytoplasm is the jelly-like substance that fills cells. It contains all the internal components of a cell,
called organelles, except for the nucleus. Clear and composed of 80% water, the cytoplasm is the
location for most of a cell's internal functions. Cytoplasm is responsible for moving materials
throughout the cell and aids in cell replication. It holds of the chemicals and other materials that
are necessary for the life and growth of the cell. It serves to maintain the shape and structure of the
cell, and also allows the cell to move. Cytoplasm is composed of three major elements: cytosol,
cytoplasmic inclusions and organelles.
Cytosol is the component that is most responsible for the structure of the cell. Composed of water,
salt and organic molecules, cytosol is everything not contained within organelles. The cytosol
makes up most of the cytoplasm and contains the filaments that form the cytoskeleton, which is
what forms the shape of the cell and allows it to move. Another major function of the cytosol is to
facilitate the movement of materials throughout the cell and between organelles.
Cytoplasmic inclusions are contained in the cytosol, but are considered separate entities. They are
not present in all cells and vary in their content. Inclusions in the cytosol include stored nutrients,
cell waste and secretory materials and pigment granules. The cytoplasm is responsible for moving
nutrients to the organelles where they are used for energy. It also facilitates the removal of waste
from the cell.
Organelles are structures within the cell that perform a specific function. The cytoplasm serves to
hold the organelles in place. Literally meaning "little organ", organelles are usually enclosed in their
own lipid bilayer. There are many cell components that qualify as organelles. The two major
organelles found in most eukaryotic cells are mitochondria and chloroplasts. Mitochondria supply
energy to the cell and direct its growth. Chloroplasts are found in plant cells and extract energy
from light sources. They also remove oxygen from carbon dioxide and water.