Lipids

Question 1

What are triglycerides?

Answer 1

The major form of lipids in food and in the body, composed of three fatty acids attached to a glyceride backbone

Question 2

Define hydrophobic.

Answer 2

Insoluble in water

Question 3

What does lipophilic mean?

Answer 3

Attracted to fat and fat solvents; fat-soluble

Question 4

What is hydrophilic?

Answer 4

Can mix with or dissolve in water

Question 5

Define lipophobic.

Answer 5

Adverse to fat solvents; insoluble in fat and fat solvents

Question 6

What are phospholipids?

Answer 6

Compounds consisting of a glycerol molecule bonded to two fatty acids and a phosphate group

Question 7

What are sterols?

Answer 7

A category of lipids that includes cholesterol, characterized by multiple ring structures

Question 8

What are fatty acids?

Answer 8

Compounds containing a long hydrocarbon chain with a carboxyl group (–COOH) at one end

Question 9

What does chain length refer to in fatty acids?

Answer 9

The number of carbons that a fatty acid contains

Question 10

Define saturated fatty acid.

Answer 10

A fatty acid completely filled by hydrogen with all carbons linked by single bonds

Question 11

What is an unsaturated fatty acid?

Answer 11

A fatty acid in which the carbon chain contains one or more double bonds

Question 12

What is a monounsaturated fatty acid (MUFA)?

Answer 12

A fatty acid in which the carbon chain contains one double bond

Question 13

Define polyunsaturated fatty acid (PUFA).

Answer 13

A fatty acid in which the carbon chain contains two or more double bonds

Question 14

What is a cis fatty acid?

Answer 14

Unsaturated fatty acid with hydrogens on the same side of the double bond, causing a bend in the chain

Question 15

Define trans fatty acids.

Answer 15

Unsaturated fatty acids with hydrogens on opposite sides of the double bond, straightening the chain

Question 16

What is hydrogenation?

Answer 16

A chemical reaction in which hydrogen atoms are added to carbon–carbon double bonds

Question 17

What is conjugated linoleic acid (CLA)?

Answer 17

A polyunsaturated fatty acid with alternating single and double bonds

Question 18

What is elongation in the context of fatty acids?

Answer 18

Addition of carbon atoms to fatty acids to lengthen them

Question 19

What does desaturation mean?

Answer 19

Insertion of double bonds into fatty acids

Question 20

Define omega-9 fatty acid.

Answer 20

Any polyunsaturated fatty acid with the first double bond between the ninth and tenth carbon atoms

Question 21

What are omega-3 fatty acids?

Answer 21

Polyunsaturated fatty acids with the first double bond between the third and fourth carbon atoms

Question 22

What defines omega-6 fatty acids?

Answer 22

Polyunsaturated fatty acids with the first double bond between the sixth and seventh carbon atoms

Question 23

What are nonessential fatty acids?

Answer 23

Fatty acids that the body can synthesize and do not need to be consumed

Question 24

What are eicosanoids?

Answer 24

A class of hormone-like substances formed from long-chain fatty acids

Question 25

What is linoleic acid?

Answer 25

An essential omega-6 fatty acid with 18 carbon atoms and 2 double bonds

Question 26

Define alpha-linolenic acid.

Answer 26

An essential omega-3 fatty acid with 18 carbon atoms and 3 double bonds

Question 27

What is glycerol?

Answer 27

An alcohol with three carbon atoms, forming the backbone of triglycerides

Question 28

What is an ester?

Answer 28

A chemical combination of an organic acid and an alcohol

Question 29

Define esterification.

Answer 29

A condensation reaction creating an ester from an organic acid and an alcohol

Question 30

What are diglycerides?

Answer 30

Molecules composed of glycerol combined with two fatty acids

Question 31

What are monoglycerides?

Answer 31

Molecules composed of glycerol combined with one fatty acid

Question 32

What are adipocytes?

Answer 32

Fat cells

Question 33

What is adipose tissue?

Answer 33

Body fat tissue

Question 34

Define visceral fat.

Answer 34

Fat stores that cushion body organs

Question 35

What is subcutaneous fat?

Answer 35

Fat stores located under the skin

Question 36

What is lanugo?

Answer 36

Soft, downy hair that covers a normal fetus and appears on semi-starved individuals

Question 37

What happens during oxidation of unsaturated fatty acids?

Answer 37

Oxygen attaches to the double bonds, leading to rancidity

Question 38

What is a phosphate group?

Answer 38

A chemical group (–PO4) with phosphorus bonded to four oxygens

Question 39

What is choline?

Answer 39

A nitrogen-containing compound part of phosphatidylcholine and acetylcholine

Question 40

What is lecithin?

Answer 40

A phospholipid in the body that contains choline

Question 41

What are micelles?

Answer 41

Tiny emulsified fat packets that can enter enterocytes

Question 42

Define lipoprotein.

Answer 42

Complexes that transport lipids in the lymph and blood

Question 43

What is a chylomicron?

Answer 43

A large lipoprotein particle formed in intestinal cells after fat absorption

Question 44

What are very-low-density lipoproteins (VLDLs)?

Answer 44

Triglyceride-rich lipoproteins formed in the liver

Question 45

What are intermediate-density lipoproteins (IDLs)?

Answer 45

Lipoproteins formed when triglycerides are stripped from VLDL

Question 46

Define low-density lipoproteins (LDLs).

Answer 46

Cholesterol-rich lipoproteins from the breakdown of IDL

Question 47

What are high-density lipoproteins (HDLs)?

Answer 47

Blood lipoproteins with high levels of protein and low levels of triglycerides