Download Macromolecules

Cells…
Homeostasis
• Maintaining a
cells internal
environment.
• CELL
MEMBRANE
• When you sweat
Fluid Mosaic Model
Means it can move!
Phospholipids
• Tails—scared of H2O
Phosphate
– Hydrophobic
• Heads—Love H2O
– Hydrophilic
• Makes a bilayer
Fatty acid
Cell Membrane
• Separates
• Made of phospholipids
and other
macromolecules
(protein and carbs)
• Selectively permeable
– Only allows certain
things in and out
Diffusion and Osmosis
WATER, WATER
EVERYWHERE
• Water is the 2nd most important thing in the
body….the only thing that beats it is
oxygen.
SO……
• You can live for weeks without food, but only
about 3 days without water.
• YOUR BODY NEEDS WATER TO CARRY ON
ITS PROCESSES…And in order for the water to
move through the cells of our body two
processes take place.
Osmosis and Diffusion
OSMOSIS
• the movement of WATER
from an area of high water
concentration to an area of
low water concentration.
The MORE water the
LESS molecules
RIGHT???? SO……
In this picture water is
moving left to right,
from an area where
there is high amounts
of water to an area
where there is low
amounts of water.
HIGH TO LOW!!
DIFFUSION
• MOLECULES spread from
areas of high molecule
concentration to areas of low
molecule concentration.
Let’s Review Water…..
• Osmosis……The movement of
WATER from an area of high
water concentration to an area
of low water concentration
• Diffusion……The movement of
MOLECULES from an area of
high molecule concentration to
an area of low molecule
concentration.
Transporting “Stuff” In and Out
of the Cell
• Passive Transport:
DIFFUSION- If the
molecules are small
enough.
What happens though if
things need to pass, but
can’t get through???
Facilitated Diffusion
• If molecules are too big to
pass through the
membrane, but still are
going HIGH to LOW!
• They need a facilitator—a
helper!
Active Transport: If substances
are going LOW to HIGH!
They use ATP!!
Where does ATP come from?
Active Transport
ENZYMES as CATALYSTS
• "Catalyst" a substance that
increases the rate of a
chemical reaction, and is
never changed or used up
by the chemical reaction.
THIS HAPPENS
MUCH FASTER,
BECAUSE OF
THE ENZYME.
WHAT IS AN ENZYME?
• A PROTEIN that makes a
chemical reaction go faster!
• Affected by temperature and pH.
temps- speed up enzymes
temps- slow enzymes down
Lock and Key
Induced Fit- Making them fit together
Macromolecules
• Proteins— Most important
macromolecule. Makes up
most of our cells. Made up of
amino acids.
aa – aa – aa – aa = protein
• Carb—Major energy source
of cell
Macromolecules
• Lipids— FATS– build up the
cell membrane (phospholipid
bilayer).
• Nucleic Acids– DNA and
RNA—heredity.