Transcript 2.3 LIPIDS Lipid Examples • • • • a. fats b. fatty acids c. triglycerides d. phospholipids –cell membranes • e.

2.3 LIPIDS
Lipid Examples
•
•
•
•
a. fats
b. fatty acids
c. triglycerides
d. phospholipids –cell
membranes
• e. steroids (including cholesterol)
LIPIDS
• NONPOLAR
• Hydrophobic“water fearing”
• Do not dissolve
in water
Lipids
• C-H atoms
linked by nonpolar covalent
bonds
• H:O ratio is
greater than
2:1
Count H:O
•CH3(CH2)4C=CCH2
C=C(CH2)7COOH
•H = 28
•O = 2
FATS
• Composition: Large lipid
molecule made of fatty acids
and glycerol
• Hydrophobic – “water avoiding”
• Purpose: energy storage
Fat = 3 fatty acids + 1 glycerol =
triglyceride
Triglycerides
• Glycerol backbone
• 3 fatty acids
Fats
• Fatty acid(s)
attached to glycerol
• Triglycerides are
most common
•
Triglyceride Dehydration Sythesis Animation
(HOW MANY WATERS
FORMED?)
Fatty Acids
Fatty Acids
• Different ways to write the
formulas
TYPES OF FATS
Oils
Soft Margarine
Solid butter, lard, Crisco
waxes
steroids
SUMMARY OF FATS
• Saturated
• Unsaturated
• solid at room
temperature
• found mostly in
animals
• no double bonds
between carbons
• liquid at room
temperature
• found mostly in
plants
• double bonds
found between
carbons
Saturated Fatty Acid
• All single bonds between C’s
•
•
•
•
•
•
H H H H H H H H H OH
| | | | | | | | | |
H-C-C-C-C-C-C-C-C-C-C=0
| | | | | | | | |
HHHHHHHHH
Monounsaturated Fat
• Note one double bond C=C
• H H H H H H H H OH
• | | | | | | | | |
• C=C-C-C-C-C-C-C-C=0
• |
| | | | | |
• H
H HHHHH
Polyunsaturated Fat
• More than one double bond
•
•
H HHH
| | | |
H
|
OH
|
=C-C-C-C-C=C-C-C=0
• H-C-C
•
•
|
H
| | |
H H H
|
H
• Saturated Fats
Unsaturated
Fats
“Trans” Fats have been
hydrogenated
• Made when manufacturers add
hydrogen to vegetable oil--a
process called hydrogenation.
• Hydrogenation increases the shelf
life and flavor stability of foods
containing these fats.
H on other
side
• Trans Fatty Acid
H
|
-C=C|
H
• Saturated Fatty Acid
H H
| |
-C - C| |
H H
• Unsaturated Fatty
Acid
H H
l l
-C = C-
Trans Fat
• can be found in
vegetable shortenings
• some margarines
• Crackers
• Cookies
• snack foods
• foods made with or
fried in partially
hydrogenated oils.
AVOID
• Trans fats should be avoided as much
as possible in our diet.
• When trans fats are exposed to heat
and oxygen during the frying process,
the results are the worse possible
combination of unhealthy fatty acids.
• (Worse than fats like butter or lard.)
Saturated Fat
• All single bonds-solid
• animalfats
Unsaturated Fat
• Has one double bond-soft
margarine
• Note how it buckles with a
double bond
CH3CH=CHCO2H
Saturated Fats
• * Double
bonds place kinks in
hydrocarbon chains and
kinked hydrocarbon chains
have lower melting points than
not kinked hydrocarbon
chains.
Polyunsaturated Fat
• Has more than one double bond
• CH3(CH2)4C=CCH2C=C(CH2)7
COOH
• Olive oil
• Mazola oil
LIPIDS
LIPIDS
• Unsaturated Fat
Phospholipids
• STRUCTURE: Also
contain phosphate and
have 2 fatty acids instead
of 3
• PURPOSE: Cell
membranes (protect and
regulate cell functions)
Phospholipids
• Main components of cell membranes
Phospholipid placed in water forms a micelle
(water heads toward water and oil ends inward)
LIPID: Phospholipids
• Cell membranes =
• phospho heads (out)
• and lipid tails (in)
Micelle
Has
hydrophobic
and
hydrophilic
ends
Phospholipid
• diglyceride-a
phosphate
takes the
place of one
of the fatty
acids
Waxes
• STRUCTURE: 1 fatty acid +
alcohol
• More hydrophobic
• Good coating for fruits and
insects
WAXES
LIPID: steroid
• Basic structure (4 fused rings)
• cholesterol
• testosterone
• progesterone
• estrogen
• PURPOSE:
Cell
membranes
and
steroids
(example:
male and
female
hormones)
LIPIDS
Progesteronestarts menstrual
cycle
Testosteronesecondary male sex
characteristics
Steroids: note the rings
Cholesterol
• Is not the “bad guy”
• needed for sex hormones,
vitamin D, and cell
membranes
Cholesterol
• Assume Carbon Atoms where non
marked
• eggs are not the reason
people have high cholesterol
(exercise or lack of it is more
of a factor)
LDL and HDL
• LDL (low density
lipoprotein)-losers
• is the “bad guy”
• deposition of
“cholesterol” on
the walls of
someone’s
arteries.
• HDL (high density
lipoprotein)-heroes
• is the “good guy,”
• carrying
“cholesterol” out of
the blood system
Explain this picture
Atherosclerosis Thickening and
loss of elasticity of arterial walls.
-lipid deposition and thickening cell
layers within arteries.
3.10 Anabolic Steroids
• Made of synthetic variants of
male hormone testosterone
• Build muscle and bone mass
Anabolic Steroids
• Purpose as a prescription drug:
Treat general anemia and diseases that
destroy body muscle
EX: treatment of weight loss in HIVinfected individuals.
EX: treat delayed puberty
EX: Their primary use is to promote
weight gain and muscle development in
farm animals.
Mike Tyson
• NEGATIVES:
“ROID
RAGE”violent mood
swings
• Can we say
“Mike eat-anear Tyson?”
Mark McGuire
-Broke
his HR
record
-But admitted to
using
androstenedione
(“andro”)
Barry Bonds
Made With THG - Animation
• (TetraHydroGestrinone)
is the steroid at the
heart of the BALCO
scandal in Major
League Baseball.
• Barry Bonds, Jason
Giambi, and Gary
Sheffield.
Barry Bonds
• When Bonds entered
the league in 1986,
he was a wiry
phenom listed at 6foot-1, 185 pounds.
• In the 2001 season,
he was 6-2 and
pushing 230 -- a
linebacker in a
baseball uniform.
“ANDRO” CONS
•
•
•
•
•
•
Depression
acne
high blood pressure women-beards
reduced sex drive
Infertility
enlarged breasts-men
liver cancer
shrunken testicles
Against the Law
• The Anabolic Steroids
Control Act of 1990
placed anabolic steroids
into Schedule III of the
Controlled Substances
Act.