Lipids: Fats & Oils
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Transcript Lipids: Fats & Oils
Lipids
Hydrophobic molecules
Do NOT consist of polymers
Function:
energy storage
cell membrane
protection - cushions organs
insulates body
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2003-2004
Structure of Fat
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What are lipids composed of?
1 glycerol + 3 fatty acids lipids (triglycerides)
Vary in length and number and location
of double bonds
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How are lipids made and broken down?
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How are lipids made?
Broken down?
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Saturated Fats
Mostly animal fats
solid at room
temperature
Saturated with
hydrogen
All single bonds
Can be tightly
packed
Limit the amount in
your diet
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Unsaturated fats
Plant, vegetable & fish
fats (oils)
liquid at room
temperature
the fat molecules
don’t stack tightly
together
Double bond causes a
kink
Better choice in your
diet
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Saturated vs. Unsaturated Examples
saturated
unsaturated
Meat
Butter
Ice Cream
Cookies
Animal Fat
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Olive oil
Canola Oil
Avocado
Nuts
Seafood
Soy
2003-2004
Other lipids in biology
Cell membranes are made out of phospholipids
2 fatty acid tails & a phosphate group
heads are on the outside touching water
“like” water (hydrophilic)
tails are on inside away from water
“scared” of water (hydrophobic)
forms a barrier
between the cell
& the outside
Regents Biology
2003-2004
Phospholipid structure
CH2
+
N(CH )
3 3
Choline
CH2
O
O
P
O–
Phosphate
O
CH2
CH
O
O
C
O C
CH2
Glycerol
O
Fatty acids
Hydrophilic
head
Hydrophobic
tails
Figure 5.13
(a) Structural formula
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(b) Space-filling model
(c) Phospholipid
symbol
10
The structure of phospholipids
Results in a bilayer arrangement found in
cell membranes
WATER
Hydrophilic
head
WATER
Hydrophobic
tail
Figure 5.14
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Other lipids in biology
Steroids, Ex: Cholesterol
Carbon skeleton of 4 fused rings
good molecule in cell membranes
make hormones from it
including sex hormones
but too much cholesterol in blood may
lead to heart disease
H3C
CH3
CH3
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HO
CH3
CH3
Other lipids in biology
Waxes
Bees, ears, shiny leaves,
shiny feathers, hair
Repels water
For protection
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