Download Lipids PP

Lipids! But first…
Do Now: 10.24.
OBJECTIVE:
1. Describe the structure, characteristics, and functions
of lipids.
TASK:
0: Pass forward enzyme labs: name on each sheet!
Melezitose has the chemical formula C18H32O16.
1. What type of macromolecule is it?
2. How many monomers does it contain?
3. What is the chemical formula of polypeptide chain of
101 glycine amino acids? (Each glycine = C3NO2H5)
Lipids: What’s a Lipid anyhow?
• Lipids come in a variety of shapes and
sizes.
• The one thing all lipids have in common is
the fact that they can’t dissolve in water.
They’re hydrophobic.
Primary function: A lipid bilayer (the cell
membrane) surrounds EVERY LIVING
CELL
Secondary Function: Long-Term
Energy Storage
Fats and oils can
store lots of
energy.
Lipids also store
hydrophobic
vitamins, like
Energy Storage
What Else do Lipids do?
Steroid Hormones /
Endocrine Functions
Estrogen
is the
female
sex
hormone
in
humans.
What Else do Lipids do?
Structure
Honeybee
hives are
made out
of a type
of lipids
called
waxes
What Else do Lipids do?
Defense
Earwax
helps
prevent
bacterial
infections
Cell membranes are made of
phospholipids
Hydrophilic “head”
Hydrophobic “tail”
A Cell Membrane has lots of
phospholipids
Cell Membrane = Phospholipid Bilayer
Hydrophilic
Hydrophobic
Hydrophilic
Lipid Monomers?
• Lipids are not truly made of repeating
monomers, like other macromolecules.
• Fatty acids are sometimes called the
monomers of lipids because they are the
building blocks of many (but not all!) lipids
Aren’t Fats bad for you?
Yes and No…
Trans-fatty acids in
some processed
foods have been
linked to heart
disease
But some are healthy
Omega-3 fatty
acids common
in fish have
been shown to
HELP
cardiovascular
health!
Fat in the Diet
• Saturated fats contain only C-C single bonds…
they are saturated with Hydrogen. Usually solid
at room temperature (e.g. butter, pork fat, etc.)
• Unsaturated fats have one (mono) or more
(poly) C=C double bonds. Usually liquid at
room temperature (e.g. vegetable oils)
• In general, unsaturated fats are more healthful
than saturated ones
Careful – They store a lot of
energy!
The bottom line on lipids
• Lipids are NOT soluble in water.
• Lipids are not truly made of monomers like the
other macromolecules. (Fatty acids?)
• Lipids have many functions, from earwax to
hormones.
• Lipids are used for LONG-TERM energy
storage, since they can’t be used directly by
cells
• Cell membranes are made
of a lipid bilayer.