Transcript Cell Differentiation PowerPoint

Cell Differentiation
What makes us so different, but
still the same.
What do you find in
plant cells that you do
not find in animal
cells?
What do you find
in animal cells
that you do not
find in plant
cells?
Not all cells are created equal…
• We know the difference between a plant
and animal cell, but are all plants and
animals exactly the same?
Why Not?
What is cell differentiation?
• cellular differentiation
is the process by
which a less
specialized cell
becomes a more
specialized cell type.
Why differentiate cells?
• Because the various cells of each plant
and animals need to perform different
functions!
– Differentiation dramatically changes a cell's
size, shape, membrane potential, metabolic
activity, and responsiveness to signals.
How do cells differentiate?
• Cellular differentiation almost never
involves a change in the DNA sequence
itself.
– Thus, different cells can have very different
physical characteristics despite having the
same genome
• These changes are largely due to highly
controlled modifications in gene
expression.
Some different plant cells
• Roots, Stems,
and leaves need
to perform
different
functions, so the
cells will be
different.
Leaf cells
• Leaves main role is
performing
photosynthesis.
• That means these
cells will be packed
with chloroplasts.
Plant Stem Cells
• Plant Stem cells need to
be able to transport
water and nutrients to
various parts of the plant.
• These cells form clusters
of tubes for transport.
– The tubes are known as
Xylem and Phloem.
– They provide structure
for the plant, just like
the skeleton provides
structure for animals.
Root cells
• Root cells need to be
able to grow in the
search for and absorb
water & minerals.
Muscle cells
• Muscle cells
are designed
to contract
and relax
allowing for
movement.
Nerve cells
• Nerve cells are
designed to
receive and
transmit impulses
from one area to
another.
Blood
• Blood is
responsible
for
transporting
various
materials to
and from the
cells.
•It also patrols the body
as part of the defense
system.
Blood
• Red blood cells are
responsible for transporting
oxygen to cells throughout
the body.
– These cells have NO nucleus.
It is pushed out so there is
more hemoglobin the protein
that holds onto oxygen.
Blood
• Platelets are critical for
clotting when blood vessels
are injured. Platelets are
fragments of a bone
marrow cell – so they do
not contain a nucleus.
• White blood cells are the
bodies defenders against
the invaders such as
bacteria. Larger than red
blood cells.
Epithelial cells
• Epithelial cells
make up the
tissues
covering the
body as well as
lining the
organs and
cavities of the
body.
A skin cell versus a Throat cell