Transcript The Animal Cell

The Animal Cell
The building blocks for all animals
Animal Cell
We will be discussing 9 organelles
of the animal cell:
Wonders of the Cell
Cell Membrane
When you think about a membrane, imagine it
is like a big plastic bag with some tiny holes.
That bag holds all of the cell pieces and fluids
inside the cell and keeps any nasty things
outside the cell. The holes are there to let some
things move in and out of the cell. The cell
membrane is not one solid piece. Everything in
life is made of smaller pieces and a membrane
is no different.
Cell Membrane
Nucleus
The cell nucleus is like the brains of the cell. It
helps control eating, movement and reproduction.
If it happens in a cell, chances are the nucleus
knows about it. The nucleus is not always in the
center of the cell. You probably won't find it near
the edge of a cell because that might be a
dangerous place for the nucleus to be. It will be a
big dark spot somewhere in the middle of all of the
cytoplasm. The cytoplasm is the fluid that fills
cells, it is a complex mixture of water, gasses,
wastes, nutrients which supply the cells needs.
Nucleus
Endoplasmic Reticulum
Another organelle in the cell is the endoplasmic
reticulum (ER). In the same way that the nucleus acts
as the cell brain, the ER works as a packaging
system. It does not work alone. ER works closely with
the Golgi apparatus, ribosomes, RNA, mRNA, and
tRNA. It creates a network of membranes throughout
the entire cell. The ER may also look different from
cell to cell, depending on the cell's function.
There is rough ER and smooth ER .
Smooth ER has its purpose in the cell. It acts as a
storage organelle. It is important in the creation and
storage of steroids. Rough ER are very important in
the synthesis (making) and packaging of proteins.
Endoplasmic Reticulum
Mitochondria
The mitochondria are known as the powerhouses of
the cell. They are the organelles that act like a
stomach and small intestine which take in nutrients,
breaks them down, and creates energy for the cell.
The process of creating that energy is known as
cellular respiration. The mitochondria is shaped
perfectly to maximize its efforts. Mitochondria are very
small organelles. You might find cells with several
thousand mitochondria. If the purpose of the cell is to
transmit nerve impulses there will be fewer
mitochondria than in a muscle cell that needs loads of
energy. If the cell feels it is not getting enough energy
to survive, more mitochondria can be created.
Mitochondria
Ribosomes
Cells need to make proteins. Those proteins might be
used as enzymes or as support for other cell
functions. When you need to make proteins, you look
for ribosomes. Ribosomes are the protein builders or
the protein synthesizers of the cell. They are like
construction guys who take one amino acid at a time
and build long protein chains. You might find them
floating in the cytoplasm. Those floating ribosomes
make proteins that will be used inside of the cell.
Other ribosomes are found on the endoplasmic
reticulum. Those attached ribosomes make proteins
that will be used inside the cell and proteins made for
export (outside the cell).
Ribosomes
Golgi Complex
The Golgi apparatus or Golgi complex is found in most
cells. It is another packaging organelle like the
endoplasmic reticulum. While layers of membranes may
look like the rough ER, they have a very different
function. The Golgi complex gathers simple molecules
and combines them to make molecules that are more
complex. It then takes those big molecules, packages
them in vesicles and either stores them for later use or
sends them out of the cell. It is also the organelle that
builds lysosomes.
Golgi Complex
Lysosomes
You will find organelles called lysosomes in nearly
every animal-like cell. They exist in the cell to digest.
They might be used to digest food or break down the
cell when it dies. A lysosome is basically a specialized
vesicle holding a variety of enzymes. The enzyme
proteins are first created in the rough ER. Those
proteins are packaged in a vesicle and sent to the
Golgi apparatus. The Golgi then does its final work to
create the digestive enzymes and pinches off a small,
very specific vesicle. That vesicle is a lysosome. From
there the lysosomes float in the cytoplasm until they
are needed.
Lysosomes
Cytoplasm
Cytoplasm is the fluid that fills a cell. Scientists used to
call the fluid protoplasm. The organelles of the cell are
suspended in the cytosol. While you will discover that
the microfilaments and microtubules set up a "skeleton"
of the cell, the cytosol fills the spaces. The cytoplasm
has many different molecules dissolved in solution. You
may discover 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.
Cytoplasm
Food Vacuole
Vacuoles are storage bubbles that are found in cells.
They are found in both animal and plant cells but are
much larger in plant cells. Vacuoles might store food or
any variety of nutrients the cell would need to survive.
They might even store waste products so that the rest
of the cell is protected from contamination. Eventually
those waste products would be sent out of the cell.
Vacuole