Cell wall - s3.amazonaws.com

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Transcript Cell wall - s3.amazonaws.com

How can we see cells?
Cells are two
small to be
seen with
the naked
eye so we
must use a
microscope
What is a Microscope?
A microscope is an
instrument that
makes small objects
look larger
A compound
microscope contains
more than one lens
How do Microscopes Work?
Some microscopes use
lenses to focus light onto
an object
The lenses in light
microscopes are similar to
the clear curved pieces of
glass used in eyeglasses
Section 2: What is inside a cell?
Organelles –
tiny cell
structures
that carry out
specific
functions
within the cell
What is the structure surrounding
the cell?
Cell wall - a rigid
layer of nonliving
material that
surrounds the
cells of plants and
some other
organelles
What is the cell wall made of?
Cellulose – a
tough, yet
flexible,
material
Wood contains
a lot of
cellulose
What is the function of the cell
wall?
A plant’s cell wall
helps to protect
and support the
cell
Cell walls allow
trees to stand so tall
If the cell wall is so stiff can
materials still pass through the cell
wall?
Yes, many
materials, including
water and oxygen,
can pass through
the cell wall
What is just inside the cell wall?
Cell membrane –
controls what substances
come into and out of a cell
All cells have cell
membranes
How does the cell membrane allow
things to pass through?
There are tiny
pores in the
membrane that
allow things to pass
through like a
window screen