Lipids part 1 Flashcards by Eulivanne Rose Anduyan

T or F: Lipids share a common structural feature

False, they share a common PHYSICAL property, they are hydrophobic

How well did you know this?

Not at all

Perfectly

With the context that Lipids are HYDROPHOBIC & NONPOLAR molecules…

Are lipids soluble in polar solvents?

No, lipids are only SOLUBLE in NONPOLAR SOLVENTS.

How well did you know this?

Not at all

Perfectly

Lipids: Biological Functions (9)

Storage of Energy

Insulation from Environment

Water Repellant

Buoyancy control and acoustics in marine mammals

Membrane structure

Cofactors for Enzymes

Signaling Molecules

Pigments

Antioxidants

How well did you know this?

Not at all

Perfectly

Cofactors for enzymes (2)

Vitamin K: blood clot formation
Coenzyme Q: ATP synthesis in mitochondria

How well did you know this?

Not at all

Perfectly

Signaling Molecules (4)

Paracrine hormones (act locally)
Steroid hormones (act body-wide)
Growth factors
Vitamins A and D (hormone precursors)

How well did you know this?

Not at all

Perfectly

Red and Yellow causing Lipids

Canthaxanthin (red)

Zeaxanthin (yellow)

How well did you know this?

Not at all

Perfectly

Type of lipid in the carboxylic acid family

Fatty Acids

How well did you know this?

Not at all

Perfectly

Type of lipid consisting of Fatty Acids + Alcohols

Waxes

How well did you know this?

Not at all

Perfectly

Type of lipid consisting of 3 Fatty acids + glycerol

Triglycerides

How well did you know this?

Not at all

Perfectly

Type of lipid consisting of 2 Fatty acids + glycerol + phosphate + X

Phospholipids and glycolipids

How well did you know this?

Not at all

Perfectly

Type of lipid which are derivatives of the fatty acid ARACHIDONIC ACID

Eicosanoids

How well did you know this?

Not at all

Perfectly

Type of lipid which are derivatives of cholesterol

Steroids

How well did you know this?

Not at all

Perfectly

Formed from phospholipids and glycolipids

Membranes

How well did you know this?

Not at all

Perfectly

Major Categories of Biological Lipids (8)

FA - Fatty Acids
GL - Glycerolipids
GP - Glycerophospholipids
SP - Sphingolipids
ST - Sterol Lipids
PR - Prenol Lipids
SL - Saccharolipids
PK - Polyketides

How well did you know this?

Not at all

Perfectly

Major categories based on structure and function

Lipids that contain fatty acids (complex lipids)
-Storage lipids
-Membrane lipids

Lipids that do not contain fatty acids
- Cholesterol
-Vitamins
-Pigments

How well did you know this?

Not at all

Perfectly

The process in which esters are hydrolyzed under basic conditions (NaOH, KOH)

Saponification

How well did you know this?

Not at all

Perfectly

Esters that undergo hydrolysis in basic solution to yield two or more smaller molecules

Saponifiable lipids

a. Simple lipids (fatty acid+alcohol) includes waxes and triglyceride.
b. Complex lipids (fatty acid +alcohol + other compounds) and includes phosphoglycerides and sphingolipids

How well did you know this?

Not at all

Perfectly

Isoprenoids, Steroids, prostaglandines are nonsaponifiable lipids cannot be hydrolyzed into smaller components why?

Because nonsaponifiable lipids are not esters.

How well did you know this?

Not at all

Perfectly

Among the SIMPLE LIPIDS there are:

Fats and Oils
and
Waxes

What do they yield?

Fats and Oils yield fatty acids AND GLYCEROL

Waxes yield fatty acids AND LONG CHAIN ALCOHOL

How well did you know this?

Not at all

Perfectly

Among the COMPOUND LIPIDS there are:

Phospholipids
and
Glycolipids

What do they yield?

Phospholipids yield:
fatty acids
GLYCEROL or SPHINGOSINE
PHOSPHORIC ACID
AMINO ALCOHOL or AMINO ACID

Glycolipids yield:
fatty acids
SPHINGOSINE
CARBOHYDRATE (upon hydrolysis)

How well did you know this?

Not at all

Perfectly

In long chain monocarboxylic acids there are two parts:

Nonpolar, hydrophobic tail (water ____)
Polar, Hydrophilic head (water ____)

Hydrophobic tail (water insoluble)
Hydrophilic head (water soluble)

How well did you know this?

Not at all

Perfectly

Most Fatty Acids contain how many Carbon atoms?

12-18

How well did you know this?

Not at all

Perfectly

Saturated Fatty Acid General Formula:

CH3(CH2)nCOOH

How well did you know this?

Not at all

Perfectly

Unsaturated Fatty acid traits(2)

At least one carbon-to-carbon double bond;

Double bonds found are usually in cis-configuration

How well did you know this?

Not at all

Perfectly

Essential fatty acids (2)

Linoleic and Linoleic

Two types of unsaturated fatty acids (2)

Omega (w) - 3 fatty acids - An unsaturated fatty acid with its endmost double bond three carbons away from its methyl end Omega (w) - 6 fatty acid - An unsaturated fatty acid with its endmost double bond six carbons away from its methyl end

Omega-3 fatty acids reduce the risk of cardiovascular disease by decreasing these things: (3)

blood clot formation blood triglyceride lvels growth of atherosclerotic plaque

Eicosapentaenoic acid (EPA) is a precursor for the synthesis of:

prostacyclin, inhibits clumping of platelets and thus reduces clot formation

___ a major fatty acids in the phospholipids of ___ , ___ , and ___ cells. It also reduces triglyceride levels.

Docosahexaenoic acid (DHA) Sperm, brain, retina

reduces the incidence of cardiovascular disease, it is also the precursor of DHA and EPA

a-Linolenic acid (ALA)

An essential fatty acid, required for the synthesis of arachidonic acid, the precursor for many ____ which exhibit anti-inflammatory effects. It is also an omega-6 fatty acid.

Linoleic acid prostaglandins

SFA MUFA PUFA

Saturated Fatty Acid Monounsaturated Fatty Acid Polyunsaturated Fatty Acid

Solubility ___ as the chain length ___

decreases, increases

Melting point ___ as the chain length ___ and the number of double bonds ___

decreases, decreases, increases

___ have straight-chain structures that allow their molecules to fit close together and form strong attractions A ___ into the hydrocarbon chain produces a rigid 30 degree bend.

Saturated fatty acids Cis double bond

Form by ____ of unsaturated fatty acids. Done to increase shelf life or stability at high temperature of oils used in cooking. They pack more regularly and show higher melting points than cis forms.

Trans fatty acids, partial dehydrogenation

Allows a given fatty acid to adopt an extended conformation.

Trans double bond

Trans Fatty Acids ___ low density lipoproteins and ___ high density lipoproteins

Raises, Lowers

The majority of fatty acids in biological systems. Less soluble in water than fatty acids due to esterification of the carboxylate group Less dense than water

Triacylglycerols

Solid forms of triacylglycerols. Some contain long chain saturated Fatty Acids Predominantly Saturated Animal source and Tasteless Colorless and Odorless

Fats

Liquid form of triacylglycerols Plants or Fish has a higher content of unsaturated Fatty Acid Predominantly Unsaturated Colorless and Odorless

Oils

The primary storage form of lipids.

Body fat

Fatty acids carry more energy per carbon because: Fatty acids carry less water per gram because: Fats are for long-term (months) energy needs

they are more reduced they are non polar

A triester formed from the esterification of GLYCEROL + THREE IDENTICAL FATTY ACID molecules

Simple triacylglycerol

The reacting fatty acid molecules are not all identical.

Mixed triacylglycerol

Simple triacylglycerol steps:

Tri - rootword of FA - in Tripalmitin

Mixed triacylglycerol steps:

Replace "ic acid" with "o" for the first and second fatty acids -sometimes you'll put a prefix if there are doubles Fatty acid in the third position replace "ic acid" with "-in" Dioleopalmitin (Mixed)

Recommended amounts are: total fat intake in calories 15% 10% <10%

Monounsaturated fat Polyunsaturated Saturated Fats

Good fats (3)

Monounsaturated fats Omega 3 Omega 6

Bad fats (3)

Saturated Fats Trans-monounsaturated fats

Good and Bad fats

Polyunsaturated fats

Chemical Properties of TAGs (5)

Hydrogenation Hydrolysis Halogenation Saponification Oxidation

Addition of H2 to double bonds of unsaturated fatty acids in lipids making them single bonds

Hydrogenation

Addition of water to ester bonds of lipids in the presence of strong acids or digestive enzymes called lipases

Hydrolysis

Adding of halogen across double (=) bond, increases degree of saturation A test for unsaturation High I2 number indicates high degree of unsaturation

Halogenation

Reaction of lipids with a strong base (ALKALINE HYDROLYSIS) to give glycerol and salts of the fatty acids (SOAPS) Produces: An alcohol Ionized salt which is soap which form micelles that dissolve oil and dirt particles

Saponification

Cleaning action of soap

Outer surfaces of micelles are hydrophilic so oil and fat are dispersed in the water layer and can be rinsed away DETERGENTS do not form insoluble products with hard water.

Double bonds in triacylglycerols are subject to oxidation with oxygen in air leads to C=C breakage

Oxidation

Fat and oil develops a disagreeable odor caused by hydrolysis and oxidation Under moist and warm conditions, hydrolysis of the ester linkages occurs leading to volatile acids being freed. Occurs in triglycerides containing unsaturated fatty acids

Rancidity Hydrolytic rancidity Oxidative rancidity

Compounds added to foods in very small amounts suppress rancidity. They have a greater affinity for oxygen than the lipid. Naturally occurring antioxidants used in the food industry are BHT, BHA, vitamin E and vitamin C.

Antioxidants

An ester of a saturated fatty acid and a long chain alcohol, each containing 14 to 30 carbon atoms. Insoluble and have high melting points Storage of metabolic fuel in plankton protection and pliability for hair and skin in vertebrates waterproofing of feathers in birds protection from evapotation in tropical plants and ivy used by people in lotions, ointments, and polishes

Wax