THE CELL
Part One:
The Animal Cell Organelles
What is a cell…
A cell is defined as the basic unit of all organisms.
All cells come from pre-existing cells and all
living things are composed of cells. Although
each cell is different depending on it location in
the body, they all are composed of the same
smaller components called organelles. These
membrane-bound organelles each perform a
specific task within the cell, but together they
compromise a fully functioning eukaryotic cell.
Let’s take a look at a few of these structures.
Cell Theory
According to the Cell Theory
1.
2.
3.
All organisms are composed of one or more cells
The cell is the basic unit of organization in organisms
All cells come from preexisting cells
Developed by Robert Hooke (1665) and others that
followed him.
So What’s the Difference?
Prokaryotic


No Nucleus
No Membrane-Bound
Organelles
Examples:
Virus, Bacteria
Eukaryotic


Nucleus Present
Membrane-Bound
Organelles
Examples:
Animal Cells, Protists
Nucleus
The nucleus is the
control center of the
cell.
Nuclear Membrane
Contains Genetic
Material (DNA).
Nucleolus
Bundle of DNA
Involved in the
making of
ribosomes
Cytoplasm
Liquid part of cell,
inside the cell
membrane, outside
the nucleus, that is
97% water
Suspends the cell’s
organelles
Site of chemical
reactions in the cell.
Cell Membrane
Phospholipid bilayer
with proteins
scattered throughout
Semipermeable
Regulates what enters
and leaves the cell
Ribosomes
Organelle where
proteins are
synthesized
Located on the
Endoplasmic
Reticulum
Some also free in
cytoplasm
Endoplasmic Reticulum
Extension of nuclear
membrane.
Found outside nucleus
in cytoplasm
Structure for the
assembly and
transport of proteins
Mitochondria
Known as the
“Powerhouse” of the
cell
Converts stored energy
in food to useable
energy
Has own DNA
Golgi Apparatus
Membranous, but not
attached to nucleus
Prepares proteins and other
cell products for
movement within the cell
Vacuoles
Membrane bound spaces
for temporary storage
of food, enzymes, and
other materials
Animals have many small
vacuoles
Much larger in plant cells
Lysosomes
“Trash man” of the cell
Organelles that contain
digestive enzymes which
break down large
particles for removal
from the cell
Microtubules
Thin cylinders made of
proteins
Give support and
structure to the cell
Make up the
Cytoskeleton
Centriole
A pair of cylinders
composed of
microtubules
Involved in animal cell
division by separating
the genetic material
In Summary…
In multicellular organisms, cells are highly
specialized for certain functions—even though
most contain the same types of organelles and
DNA. However, the number and kind of
organelles within the cell will determine its
specific function depending on where the cell is
located.
THE CELL
Part Two:
The Plant Cell
A Brief Intro…
Plant cells are very similar to animal cells and
therefore contain many of the same organelles.
Plant cells are more rigid in structure and the
amount of water in the cell is important in
support of the cell.
Plastids
Plastids are involved in the
storage of a variety of
different things: food,
proteins, chlorophyll
The color of the plant is
usually caused by the
contents of the plastids
Chloroplasts
A chloroplast is an example
of a plastid filled with
chlorophyll
Like mitochondria, have
their own DNA
Chlorophyll gives a plant its
green color
Chlorophyll is used by the
plant during photosynthesis
Cell Wall
Plants have an exterior cell
wall outside of their
membranes
The cell wall is composed
mainly of cellulose
Has openings (plasmodesmata) which connect
the cytoplasm of
neighboring cells
Vacuole
The vacuole of a plant cell is
similar to an animal in that
it is filled mainly of water.
The plant vacuole is much
larger and only one or two
in a cell (roughly 90% of
the cell)
Turgor Pressure and the
amount of water in the
vacuole gives support to
the cell
COMPARE