2.3 LIPIDS. Lipids C-H atoms linked by non- polar covalent bonds H:O ratio is greater than 2:1.
-
Upload
tony-frake -
Category
Documents
-
view
215 -
download
0
Transcript of 2.3 LIPIDS. Lipids C-H atoms linked by non- polar covalent bonds H:O ratio is greater than 2:1.
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 non-polar covalent bonds
• H:O ratio is greater than 2:1
Count H:O
•CH3(CH2)4C=CCH2C=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• solid at room
temperature• found mostly in
animals• no double bonds
between carbons
• Unsaturated• 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
• | | | | | | | | |
• H H H H H H H H H
•
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 H H H H H
Polyunsaturated Fat• More than one double bond• H H H H H OH • | | | | | |
• H-C-C=C-C-C-C-C=C-C-C=0
• | | | | | • 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 AcidH
|
-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
LIPIDS• PURPOSE: Cell membranes and steroids (example: male and female hormones)
Progesterone-starts menstrual cycle
Testosterone-secondary 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 muscleEX: treatment of weight loss in HIV-
infected individuals. EX: treat delayed pubertyEX: 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-an-ear Tyson?”
Mark McGuire
-Broke his HR record-But admitted to using androstenedione(“andro”)
Barry BondsMade 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 6-foot-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.