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