FATTY ACIDS

Question 1

A _________ is a naturally occurring monocarboxylic acid.

Answer 1

fatty acid

Question 2

In terms of carbon chain length, fatty acids are characterized as long-chain fatty acids (__________), medium-chain fatty acids (_________), or short-chain fatty acids
(__________).

Answer 2

a. C12 to C26
b. C8 and C10
c. C4 and C6

Question 3

A __________ fatty acid is a fatty acid with a
carbon chain in which all carbon–carbon
bonds are single bonds.

Answer 3

saturated

Question 4

___________ (C16) is the precursor for variety of long-chain fatty acids such as stearic acid, palmitoleic acid, and oleic acid.

Answer 4

Palmitic acid

Question 5

IUPAC name for palmitic acid.

Answer 5

hexadecanoic acid

Question 6

A ______________ fatty acid is a fatty acid with a carbon chain in which one carbon–carbon double bond is present.

Answer 6

monounsaturated

Question 7

_________ is classified as a monounsaturated omega-9 fatty acid, abbreviated with a lipid number of 18:1 cis-9, and is the most abundant natural monounsaturated fatty acid in plants and animals.

Answer 7

oleic acid

Question 8

IUPAC name for oleic acid.

Answer 8

cis-9-octadecenoic acid

Question 9

A ___________ fatty acid is a fatty acid with a carbon chain in which two or more
carbon–carbon double bonds are present.

Answer 9

polyunsaturated

Question 10

An ________________ is an unsaturated fatty acid with its endmost double bond three carbon atoms away from its methyl end.

Answer 10

omega-3 fatty acid

Question 11

18:3(Δ9,12,15)

_________ is plant-based essential omega-3 polyunsaturated fatty acids that must be obtained through the diet.

Answer 11

α-Linolenic acid

Question 12

20:4(Δ5,8,11,14)

___________ is a polyunsaturated omega-6 fatty acid 20:4(ω-6).

Answer 12

arachidonic acid

Question 13

18:2 (n-6) or 18:2 cis-9,12

________________ is the shortest chain n-6 fatty acid and the most common PUFA in plant oils, is a biosynthetic precursor of arachidonic acid.

Answer 13

Linoleic acid

Question 13

20:3 (n-6)

The synthesis of the __________ (20:3n-9), also known as mead acid or 5,8,11-____________, increases only when dietary intakes of omega-3 and omega-6 fatty acids are very low. Thus mead acid is one indicator of a deficiency of essential fatty acid

Answer 13

eicosatrienoic acid
Dihomo-gamma-linolenic acid (DGLA)

Question 14

The physical properties of fatty acids, and of lipids that contain them, are largely determined by __________ and _____________.

Answer 14

the length and degree of
unsaturation of the fatty acid carbon chain

Question 15

Solubility _________ as carbon chain length increases.

Answer 15

decreases

Question 16

Melting points for fatty acids are strongly influenced by both ___________ and _______________.

Answer 16

a. carbon chain length
b. degree of unsaturation (number of double bonds present)

Question 17

As carbon chain length increases, melting point _____________.

Answer 17

increases

Question 18

The greater the degree of unsaturation, the ____________ the reduction in melting points.

Answer 18

greater

Question 19

The decreasing melting point associated with increasing degree of unsaturation in fatty acids is explained by ______________ between carbon chains.

Answer 19

decreased molecular
attractions

Question 20

The double bonds in unsaturated fatty acids, which generally have the cis configuration, produce
__________ in the carbon chains of these molecules.

Answer 20

“bends”

Question 21

The greater the number of double bonds, the ______ efficient the packing.

Answer 21

less