AP Biology

Lipids: Fats & Oils

2006-2007 AP Biology

Lipids

________________________________________________

AP Biology

Lipids Lipids are composed of C, H, O

____________________________

“Family groups” _________________ _________________ _________________

____________________________ big molecules made of smaller subunits not a continuing chain

AP Biology

Fats Structure:

___________________________________ fatty acid =

long HC “tail” with carboxyl (COOH) group “head”

dehydration synthesis

H2Oenzyme

AP Biology

Building Fats Triacylglycerol

3 fatty acids linked to glycerol _______________ = between OH & COOH

hydroxyl carboxyl

AP Biology

Dehydration synthesis

H2O

H2O

H2O

H2O

enzyme

enzyme

enzyme

dehydration synthesis

AP Biology

Fats store energy Long HC chain

polar or non-polar? hydrophilic or hydrophobic?

Function: _________________

concentrated all H-C!

2x carbohydrates _________________ _________________

think whale blubber!

Why do humanslike fatty foods?

AP Biology

Saturated fats All C bonded to H No C=C double bonds

____________________ ____________________ ____________________

contributes to cardiovascular disease (atherosclerosis) = plaque deposits

AP Biology

Unsaturated fats C=C double bonds in

the fatty acids ______________________ ______________________ ______________________

the kinks made by doublebonded C prevent the molecules from packing tightly together

mono-unsaturated?poly-unsaturated?

AP Biology

Saturated vs. unsaturated_______________ _______________

AP Biology

Phospholipids Structure:

glycerol + 2 fatty acids + PO4

PO4 negatively charged

It’s just like apenguin…

A head at one end& a tail

at the other!

AP Biology

Phospholipids Hydrophobic or hydrophilic?

fatty acid tails = _____________________ PO4 head = _____________________ split “personality”

interaction with H2O is complex & very important!

Come here,No go away!Come here,No go away!

“repelled by water”

“attracted to water”

AP Biology

Phospholipids in water ____________________________________ ____________________________________

can self-assemble into “bubbles” bubble = “micelle” can also form a __________________________ early evolutionary stage of cell?

bilayer

water

water

AP Biology

Why is this important? Phospholipids create a barrier in water

define outside vs. inside they make ________________________

Tell themabout soap!

AP Biology

Steroids Structure:

4 fused C rings + ?? different steroids created by attaching different

functional groups to rings different structure creates different function

examples: _________________________

cholesterol

AP Biology

Cholesterol Important cell component

________________________________ ________________________________

including vertebrate sex hormones high levels in blood may contribute to

cardiovascular disease

AP Biology

Cholesterol

helps keep cell membranes

fluid & flexible

Important component of cell membrane

AP Biology

From Cholesterol Sex Hormones What a big difference a few atoms can make!

2006-2007 AP Biology

Let’s build some

Lipids!