M2 (Biochemistry) - Lipids

lipids

organic compound found in living organisms that is insoluble in water but soluble in nonpolar organic solvents

water

lipids are insoluble in ___

nonpolar organic solvents

lipids are soluble in ___

true

t or f: lipids do not have a common structural feature

solubility

characterization of lipids is based on ___ characteristics

triacylglycerol

lipid containing a glycerol backbone and 3 fatty acid chains

triglycerides

triacylglycerol can also be called as ___

glycerophospholipid

glycerol backbone + 2 fatty acid chains + phosphate + amino alcohol

sphingophospholipid

sphingosine backbone + fatty acid chain + phosphate + amino alcohol

sphingoglycoplipid

sphingosine backbone + fatty acid chain + carbohydrate group

energy-storage, membrane, emulsification, messenger, protective-coating

classification of lipids based on biochemical function

energy-storage

triacylglycerols

membrane

phospholipids, sphingoglycolipids, cholesterol

emulsification

bile acids

messenger

steroid hormones and eicosanoids

20

eicosanoids contain how many carbons

protective-coating

biological waxes

triacylglycerols

examples of this include fats and oils

glycerophospholipids, sphingophospholipids

types of phospholipids

glycerophospholipids

examples of this include lecithins and cephalins

sphingophospholipids

example of this is sphingomyelins

sphingoglycolipids

examples of this include cerebrosides and gangliosides

bile acids

cholic acid, deoxycholic acids

sex hormones, adrenocorticoids

steroid hormones can be classified into two

sex hormones

estrogens, androgens, progestins

adrenocorticoids

examples of this are mineralocorticoids and glucocorticoids

eicosanoids

prostaglandins, thromboxanes, leukotrienes

biological waxes

protective-coating lipid

saponifiable

type of lipids that are converted into two or more smaller molecules when hydrolysis occurs

TAG, phospholipids, sphingoglycolipids, biological waxes

examples of saponifiable lipids

nonsaponifiable

type of lipids that cannot be broken up into smaller units since they do not react with water

cholesterol, steroid hormones, bile acids, eicosanoids

examples of nonsaponifiable lipids

fatty acids

building blocks of lipids are generally called what

monocarboxylic acid

a fatty acid is a naturally occurring ___

even, unbranched

fatty acids nearly always contain an ___ number of carbon atoms and have an ___ chain

short chain

C4 to C6 fatty acids

medium chain

C8 to C10 fatty acids

long chain

C12 to C26 fatty acids

saturated

absence of double bonds

unsaturated

presence of double bonds

caproic acid

C6 saturated FA

caprylic acid

C8 saturated FA

capric acid

C10 saturated FA

lauric acid

C12 saturated FA

myristic acid

C14 saturated FA

palmitic acid

C16 saturated FA

stearic acid

C18 saturated FA

arachidic acid

C20 saturated FA

linoleic, linolenic

essential unsaturated fatty acids

linoleic acid

18:2 delta 9, 12

linolenic acid

18:3 delta 9, 12, 15

saturated

no double bonds present in the carbon chain

monounsaturated

one double bond is present in the carbon chain

polyunsaturated

two or more double bonds are present in the carbon chain

cis

naturally occurring fatty acids generally contain ___ double bonds

trans

hydrogenation converts some cis double bonds to ___ double bonds

hydrogenation

___ converts some cis double bonds to trans double bonds

inverse

relationship of solubility with carbon chain length

decreases

solubility ___ as carbon chain length increases

direct

relationship of melting point with carbon chain length

increases

melting point ___ as carbon chain length increases

saturated

which fatty acids have the higher melting point: saturated or unsaturated

inverse

relationship of double bonds with melting point

decrease

an increase in double bonds will show a ___ in melting point

solid

long-chain saturated fatty acids tend to be ___ at room temperature

liquid

long-chain unsaturated fatty acids tend to be ___ at room temperature

carboxyl end

where do you start counting when writing delta nomenclature

number of carbons

first digit in the delta nomenclature

number of double bonds

second digit in the delta nomenclature

locant numbers of double bonds

superscripts or exponents after the delta symbol

omega nomenclature

names the positioning of double bonds relative to the last carbon

alkyl end

where do you start counting when writing omega nomenclature

omega-3

examples of this include a-linolenic acid, timnodonic acid, cervonic acid

timnodonic acid

eicosapentaenoic acid or EPA

cervonic acid

docosahexaenoic acid or DHA

omega-6

linoleic acid, arachidonic acid

omega-9

oleic acid, elaidic acid