Download B) Cells

CELLS!
History of Cells
*Robert Hooke used the first microscope to
look at a thin slice of cork in 1665. He saw “a
lot of little boxes,” which reminded him of
small rooms that monks lived in called CELLS!
History of Cells
 10
years later,
Anton van
Leeuwenhoek
viewed pond water
under a microscope
and discovered
many tiny, living
creatures which he
called
“animalcules.”
History of Cells
 Today,
we know
that they were not
animals, but singlecelled organisms.
The Cell Theory
* Three scientists, Schleiden,
Schwann, and Virchow put together
what we know today as the cell
theory.
The Cell Theory
All living things are made of one or
more cells.
2. Cells are the basic unit of structure
and function in living things.
3. All cells arise from existing cells.
The Cell Theory Song - YouTube
1.
Remember where cells fit into the
levels of classification.
2 Major Categories of Cells
 Cells
Cells - Parts of the Cell Rap YouTube
 PROKARYOTES
–The smallest and simplest cells
are prokaryotes.
–They are single-celled
organisms that lack a nucleus
and other internal
compartments.
2 Major Categories of Cells
The Cell Song - YouTube
 EUKARYOTES

–The first cells with internal
compartments.
–Evolved about 2.5 billion years
ago.
–Eukaryotes include plants and
animals and have a nucleus and
other membrane bound organelles.
PROKARYOTES
 Without
separate compartments
(organelles), prokaryotes cannot
carry out many specialized
functions.
PROKARYOTES
 They
are very simple and very
small.
PROKARYOTES
 The
familiar prokaryotes that
cause infection and food to spoil
belong to a class commonly
called bacteria.
PROKARYOTES

They can live in a
range of
environments:
some do not even
need oxygen to
survive, some
make their own
food, some live in
extreme hot or
extreme cold.
PROKARYOTES
 They
can grow
and divide very
rapidly.
PROKARYOTES
 There
are no
internal
organelles, so
the cell’s
enzymes and
ribosomes are
free to move
around in the
cytoplasm.
Prokaryote Structure

Genetic material
(DNA or RNA) is a
single circular
molecule. This
loop is located
near the center of
the cell.
Prokaryote Structure

Cell Membrane
(Cytoplasmic
Membrane) that
allows certain
materials in/out
of the cell.
Prokaryote Structure

There is a cell
wall that
surrounds the cell
membrane,
providing
structure and
support.
Prokaryote Structure
 They
lack the
internal
supporting
skeleton, so
they depend on
a strong cell
wall to give the
cell shape.
Prokaryote Structure
 Some
have
flagella, long
threadlike
structures
that protrude
from the cell’s
surface and
enable
movement.
Prokaryote Structure
 Some
may
have tiny
“hairs,” cilia
for
movement.
Prokaryote Structure
 Ribosomes
make
proteins.
to
Prokaryotes things to remember
 Prokaryotes
are BACTERIA.
 Prokaryotes have NO nucleus. PRO
rhymes with NO….NO NUCLEUS!
 Prokaryotes have CELL WALLS.
EUKARYOTES
 EUKARYOTE
– an organism whose
cells have a nucleus and membrane
bound organelles.
EUKARYOTES
 Eukaryotes
Animals.
include Plants and
EUKARYOTES
 EU
rhymes with Do….Eukaryotes DO
HAVE A NUCLEUS!
Eukaryote Organelles

Cell wall – only in
plants. Composed
of proteins and
carbohydrates,
including
cellulose, it helps
support and
maintain the
shape of the cell,
protects it from
damage, and
connects it with
adjacent cells.
Eukaryote Organelles
 Chloroplast
–
only in plants.
Organelles that
use light energy
to make
carbohydrates
from CO2 and
H2O.
Eukaryote Organelles

Central Vacuole –
only in plants.
Stores water.
When the central
vacuole is full, it
makes the cell
rigid, which
enables the plant
to stand upright.
EUKARYOTES
 Cytoplasm
–
includes
everything
inside the cell
membrane, but
outside the
nucleus.
EUKARYOTES
 Flagella
and Cilia –
only in some
animal cells. Both
are used for
movement.
Flagella is like a
long tail. Cilia are
short, hair like
structures.
EUKARYOTES
 Cytoskeleton
–
provides the
interior
framework of
an animal cell,
much like a
human
skeleton.
EUKARYOTES

Cell Membrane – it
is fluid, like a soap
bubble. It
separates the
inside from the
outside of the cell.
This barrier allows
only certain
substances into the
cell and out of the
cell.
EUKARYOTES
 Nucleus
–
houses DNA. It
is like the brain
of the cell and
regulates the
cells functions.
EUKARYOTES
 Nucleolus
–
small dense
region in the
center of the
nucleus that
puts together
ribosomes.
EUKARYOTES
 Ribosomes
make
proteins.
–
EUKARYOTES

Endoplasmic
Reticulum – the
highways system of
the cell that
transports proteins.
If it has ribosomes
stuck to it, its
known as rough
E.R. If it does not
have ribosomes
stuck to it, it is
known as smooth
E.R.
EUKARYOTES
 Golgi
Apparatus –
packaging and
distribution center
of the cell.
EUKARYOTES
 Lysosomes
–
digestion
center of the
cell.
EUKARYOTES
 Mitochondria
–
The powerhouse
of the cell. By
breaking down
big molecules,
the mitochondria
makes ATP for
the cell. ATP is
energy!