Transcript Inside Cells

Inside Cells
All living things are made of cells.
Cells come in MANY shapes and
sizes.
Some organisms like bacteria are
only one-cell big. Others like a
mammal have several trillion cells.
You already know that cells are
very small.
You have to use
a microscope to
even see one.
If red blood cells were
placed end-to-end
it would take 150 cells
to equal the thickness
of a penny!
The cells in our brain, bones, heart,
and blood all have special jobs.
Even though the cells do different
jobs, they have the same basic
parts inside, called ORGANELLES.
(Write the definition of “oragnelle”)
Let’s take a tour through a cell…
(take notes as 3 columns of a graphic organizer. Label
the columns NAME, FUNCTION, CANDY)
The outside of every cell is surrounded
by the CELL MEMBRANE, which is
kinda like a thin, squishy baggie.
The job of the CELL MEMBRANE is
to decide what comes in and what
stays out. It is full of holes.
The whole inside of the cell is filled
with gooey slime called
CYTOPLASM.
The job of CYTOPLASM is to hold
the organelles in place and swish
chemicals around.
The big dark circle thing in cells is
the NUCLEUS.
The NUCLEUS is the boss – it
controls the activities of all the
other organelles.
Inside of the nucleus are many
CHROMOSOMES. They contain the
instructions for making every part
of the cell. Usually they look like
strands of spaghetti.
When the cell is ready to divide,
the CHROMOSOMES condense into
“worm” shapes and pair up. Like
twirling the spaghetti on a fork
The NUCLEUS sends out instructions
for making proteins, or repairing the
cell, or dividing the cell. These
instructions, called RNA are like
chemical text messages.
The RNA instructions go to the
RIBOSOMES. Ribosomes follow the
instructions to make different kinds of
proteins.
Ribs are made of Protein.
Ribs remind me of RIBosomes
Proteins are used to make just
about everything, not just meat
(muscle).
These proteins are shipped all over
the cell on the ENDOPLASMIC
RETICULUM (or just ER for short).
The ER is like a giant freeway system
that goes through the entire cell. The
RIBOSOMES are tiny little dots on the
ER.
The ER might deliver these
proteins to the GOLGI, that
package them for transport.
Another large part of the cell is the
VACUOLE. It stores water, and
sometimes other things.
Just like anything that is alive, cells
have waste products that need to be
recycled. This is the job of the
LYSOSOMES.
The prefix “lys” means “break apart”
So the lysosomes break apart old,
worn out parts so they can be recycled
into new stuff. They go around
“eating” stuff like pac man.
(Why do you think the name LYSOL was chosen?)
MITOCHONDRIA take the energy in
sugar and turn it into fuel that the
cell can use. They are the power
suppliers for the cell.
MITOCHONDRIA are mighty and
full of muscle (or at least there are
lots of them in muscle) Why?
CHLOROPLASTS are found only in plant
cells, but they have a job kinda like
mitochondria. They convert sunlight
to sugar, that can then be sent to the
mitochondria.
CHLOROPLASTS have a chemical
inside called chlorophyll. This
chemical is what makes plants
appear green.
Plants also have another cool feature.
They have a second outer layer called
a CELL WALL. This is what makes
plants rigid, and keeps trees from
falling over.
CELL WALLS are made of cellulose,
which can’t be digested by most
animals – that’s why it is the main
ingredient in metamucil.
The