Transcript Cells- Osmosis and Diffusion

Cells
http://www.youtube.com/watch?v=
gFuEo2ccTPA
What is a cell?
•Smallest
unit of a
living
thing.
• Cells make up Tissues which
make up Organs which make
up Organ Systems which
make up Organisms!
• Organisms are Living things!
• Makes up
organisms.
• Can be an
organism (singlecelled) creatures
or …
•…multicelled
like us!
• Most cells are
alive
• They reproduce,
grow/develop,
use/obtain energy,
and adapt to their
environment,
contain
chemicals.
Specialized cells
• Have a
specific
function
that they
serve…
http://www.youtube.com/watch?v=
I8uXewS9dJU
Discovery of the Cell
http://www.youtube.com/watch?v=
dscY_2QQbKU
Mathias Schleiden
• Discovered that plants
contain cells
Theodor Schwann
•Discovered that animals
are made up of cells.
Rudolph Virchow
•Discovered that cells
divide to create new
cells.
All of these scientists
contributed to the Cell
Theory…
•1) All living things are
made up of one or more
cells.
•2) Cells are the basic unit
of structure and function
of living things.
•3) All cells come from
pre-existing cells.
• Prokaryotic
Cells- “pro”before karyon
or kernel
• Cells without a
nucleus
• Ex.
Viral/Bacterial
cell
• Eukaryotic Cells“true karyon” or
kernel
• Cells with a
nucleus
• Ex. Plant, Animal
cells http://www.youtube.com/watch?v=
yWy4o_UfZ4A
Of course none of this would
have been possible without
Anton Van Leeuwenhoek and his early microscope!
We’ve come a long ways…
Organelle
• Tiny “organs” that
perform a specific job
(function) inside of a cell.
• Structure- how it is made,
what it is made of?
• Examples- Nucleus, Ribosomes,
Mitochondria, ER
Cell Wall
Organelles
Details, Diagrams,
Explanations
Cell Wall- not found
in ANIMAL cells pg.
173
Structure
Fibers of
carbohydrates/proteins
Cellulose- carbo fiber
Function
Support/Protection for
cell
Allows substances to
pass into cell (H20, 02,
CO2,)
Selectively Permeable
Ribosomes
Organelles
Details, Diagrams,
Explanations
Ribosomes- pg. 177
Structure
Round organelles
Found in cytoplasm,
rough ER
Small
Function
Makes proteins
Nucleus gives
instructions
Cell Membrane
• Controls what goes in/out of
cell
• Protection
• Support/Shape
Cell membrane___
1. Diffusion (passive)
• “Molecules” moving from an area
of high concentration to an area of
low concentration.
• Trying to reach a state of
“equilibrium” where all molecules
are evenly spaced!
Selectively Permeable
• Allows or “selects” certain
materials to enter/leave the cell
• Good things- Vitamins, Minerals,
Water, Oxygen
• Bad things- Viruses, Bacteria,
Pirates
Passive Transport
Requires little to no
cell energy to move
molecules
throughout the cell.
1- Diffusion
2- Osmosis
2. Osmosis (passive)
•The diffusion of
WATER!
http://www.youtube.com/watch?v=
IaZ8MtF3C6M
Osmotic pressure
• Isotonic- balanced
• Hypertonic- cells shrink, vacuoles
collapse
• Hypotonic- cells swell and burst!
Facilitated Diffusion
• Specific type of diffusion
• Passive
• Protein channels assist/allow
passage through membrane
Active Transport
• Movement through
a cell membrane
(cell wall) in which
the cell USES
energy!
Endocytosis
• Type of active transport
• Brings materials into cell by capturing into
“pockets”
Exocytosis
• Removal of materials from cell
• Pushes material out of the cell
• Active transport
Nucleus
•
•
•
•
Located in center of cell
Circular
Contains DNA/Genetic Info
The “Boss” of the cell. Controls
cell functions
Osmotic Pressure