Lipids of Physiologic Significance

Question 1

PROPERTIES OF LIPIDS

Answer 1

relatively insoluble in water and
soluble in
nonpolar solvents

Question 2

WHICH OF THE FOLLOWING IS CORRECT?
A. Lipids are important
dietary constituents not only because of the high energy value of fats
B. essential fatty acids, fat-soluble vitamins, and other
lipophilic micronutrients are contained in the fat of natural foods
C. Dietary
supplementation with long-chain ω3 fatty acids is believed to have
beneficial effects in a number of chronic diseases, including cardiovascular
disease, rheumatoid arthritis, and dementia.
D. All of the above

Answer 2

D. All of the above

Question 3

Fat is stored in

Answer 3

adipose tissue

Question 4

are esters of fatty acids

with various alcohols:

Answer 4

Simple lipids

Question 5

Which statement is incorrect?
A. Fat is stored in connective tissue,
where it also serves as a thermal insulator in the subcutaneous tissues and
around certain organs.
B. Nonpolar lipids act as electrical insulators,
allowing rapid propagation of depolarization waves along myelinated
nerves.
C. Lipids are transported in the blood combined with proteins in
lipoprotein particles
D. None of the above

Answer 5

A. Fat is stored in adipose tissue

Question 6

Fats

Answer 6

Esters of fatty acids with glycerol.

Question 7

Fats in the liquid

state.

Answer 7

Oils

Question 8

Waxes

Answer 8

Esters of fatty acids with higher molecular weight

monohydric alcohols.

Question 9

esters of fatty acids, which always contain an alcohol and one or more fatty acids, but which also have other groups.

Answer 9

Complex lipids

Question 10

Contain a phosphoric acid residue. They frequently have nitrogen-containing bases (eg, choline) and other substituents.

Answer 10

Phospholipids:

Question 11

Which is incorrect?
A. Phospholipids frequently
have nitrogen-containing bases (eg, choline) and other substituents.
B. Glycerophospholipids are type of phospholipid is which the alcohol is glycerol
C. Sphingophospholipids are type of phospholipid is which the alcohol is spinghosine, which contains a carbohydrate group
D. Glycolipids (glycosphingolipids) are fatty acid
sphingosine, and carbohydrate.

Answer 11

C. Sphingophospholipids are type of phospholipid is which the alcohol is spinghosine, which contains a carbohydrate group

sphingophospholipids it is
sphingosine, which contains an amino group.

Question 12

Example of other complex lipids except:
A. Lipoproteins
B. Sulfolipids
C. Waxes
D. amino lipids

Answer 12

C. Waxes

Question 13

formed from the hydrolysis of both simple and complex lipids.

Answer 13

Derived lipids

Question 14

Which is untrue?
A. Derived lipids are formed from the hydrolysis of both simple and
complex lipids
B. They include fatty acids, glycerol, steroids, other
alcohols, fatty aldehydes, ketone bodies,
hydrocarbons, lipid-soluble vitamins and micronutrients, and
hormones.
C. Some of these (eg, free fatty acids, glycerol) also act as
precursor lipids in the formation of simple and complex lipids.
D. Because they are uncharged, acylglycerols (glycerides), cholesterol, and
cholesteryl esters are termed neutral lipids.
E. None of the above

Answer 14

E. None of the above

Question 15

Which is correct?
A. Fatty acids occur in the body mainly as esters in natural fats and oils, but are found in the esterified form as free fatty acids, a transport form in
the plasma
B. Fatty acids that occur in natural fats usually contain an odd
number of carbon atoms.
C. Fatty acids are aliphatic carboxylic acids
D. The head may be saturated (containing no double bonds) or unsaturated (containing one or more double bonds)

Answer 15

C. Fatty acids are aliphatic carboxylic acids

Question 16

The naming system in which systematic nomenclature names the fatty acid
after the hydrocarbon with the same number and arrangement of carbon
atoms, with -oic being substituted for the final -e

Answer 16

Genevan system

Question 17

end in -anoic

Answer 17

saturated acids

for example, octanoic acid (C8),

Question 18

end in -enoic

Answer 18

unsaturated acids with double bonds
octadecenoic acid (oleic acid, C18).

Question 19

Which is true?
A. Carbon atoms are numbered from the carboxyl carbon (carbon no. 1).
B. The carbon atoms adjacent to the carboxyl carbon (nos. 2, 3, and 4) are
also known as the α, β, and γ carbons, respectively, and the terminal
methyl carbon is known as the ω- or n-carbon.
C. All of the above
D. None of the above

Answer 19

C. All of the above

Question 20

Which statement is incorrect?
A. Δ9 indicates a double bond
between carbons 9 and 10 of the fatty acid
B. ω9 indicates a double bond on
the ninth carbon counting from the ω-carbon
C. In plants, additional double
bonds can be introduced only between an existing double bond at the ω9, ω6, or ω3 position and the carboxyl carbon, leading to three series of fatty
acids known as the ω9, ω6, and ω3 families,
D. None of the above

Answer 20

C. In animals, additional double
bonds can be introduced only between an existing double bond at the ω9, ω6, or ω3 position and the carboxyl carbon, leading to three series of fatty
acids known as the ω9, ω6, and ω3 families,

Question 21

Which is incorrect?
A. Saturated Fatty Acids Contain No Double Bonds
B. Unsaturated Fatty Acids Contain One or More Double Bonds
C. All of the above
D. None of the above

Answer 21

D. None of the above

Question 22

What fatty acid contains 4 C atoms that can be find in certain fats in small amounts (especially butter). It is an end product of carbohydrate fermentation by rumen organism

Answer 22

Butyric

Question 23

How many carbon atom is Acetic acid?

Answer 23

2

Question 24

How many carbon atom in Valeric acid?

Answer 24

5

Question 25

6 carbon fatty acid

Answer 25

Caproic acid?

Question 26

How many carbon atom in Lauric acid?

Answer 26

12

Question 27

Can be found in spermaceti, cinnamon, palm kernel, coconut oils, laurel, butter

Answer 27

Lauric Acid

Question 28

14 carbon fatty acid can be found in nutmeg, palm kernel, coconut oils, butter

Answer 28

myristic

Question 29

16 carbon fatty acid

Answer 29

Palmitic

Question 30

How many carbon is Stearic Acid

Answer 30

18

Question 31

``` All are one double bond unsaturated fatty acid except? A. Palmitoleic B. Oleic C. Elaidic D. Linoleic ```

Answer 31

D. Linoleic

Question 32

Systemic name for Elaidic Acid which is a C18 with double bond on 1;9 carbon atoms

Answer 32

trans-9-octadecenoic

Question 33

Under w7 family of fatty acid that can be found in nearly all fats

Answer 33

Palmitoleic

Question 34

``` All are under w3 family except: A. Cervonic B. Timnodonic C. a-Linolenic D. y-Linolenic ```

Answer 34

D. y-Linolenic

Question 35

``` All are under w9 except A. Oleic B. Elaidic C. None of the above D. All of the above ```

Answer 35

C. None of the above

Question 36

containing one double bond

Answer 36

Monounsaturated

Question 37

Polyunsaturated

Answer 37

containing two or | more double bonds.

Question 38

derived from eicosa (20-carbon) | polyenoic fatty acids

Answer 38

Eicosanoids

Question 39

``` Eicosanoids comprises of all except: A. Prostanoids B. Leukotrienes C. Lipoxins D. None of the above ```

Answer 39

D. None of the above

Question 40

``` Prostanoids is/are: A. Prostglandins B. Prostacyclins C. Thromboxanes D. All of the above ```

Answer 40

D. All of the above

Question 41

exist in virtually every mammalian tissue, acting as local hormones; they have important physiologic and pharmacologic activities.

Answer 41

Prostaglandins

Question 42

Which statement is incorrect? A. Prostaglandins are synthesized in vivo by cyclization of the center of the carbon chain of 20-carbon (eicosanoic) polyunsaturated fatty acids (eg, arachidonic acid) to form a cyclopentane ring B. A related series of compounds, the thromboxanes, have the cyclopentane ring interrupted with an oxygen atom (oxane ring) C. Three different eicosanoic fatty acids give rise to three groups of eicosanoids characterized by the number of double bonds in the side chains D. Different substituent groups attached to the rings give rise to series of prostaglandins and thromboxanes labeled 1, 2, etc

Answer 42

D. Different substituent groups attached to the rings give rise to series of prostaglandins and thromboxanes labeled 1, 2, etc should be Different substituent groups attached to the rings give rise to series of prostaglandins and thromboxanes labeled A, B, etc

Question 43

Which statement is correct? A. the “F” type of prostaglandin has a keto group in position 9 B. the “F” type has a hydroxyl group in position 9 C. The leukotrienes and lipoxins are a third group of eicosanoid derivatives formed via the cyclooxygenase pathway D. Thromboxanes cause bronchoconstriction as well as being potent proinflammatory agents, and play a part in asthma.

Answer 43

B. the “F” type has a hydroxyl group in position 9

Question 44

Which is/are true? A. The carbon chains of saturated fatty acids form a zigzag pattern when extended at low temperatures B. A type of geometric isomerism occurs in unsaturated fatty acids, depending on the orientation of atoms or groups around the axes of double bonds, which do not allow rotation C. At higher temperatures, some bonds rotate, causing chain shortening, which explains why biomembranes become thinner with increases in temperature D. All of the above E. None of the above

Answer 44

D. All of the above

Question 45

Which is correct? A. If the acyl chains are on the same side of the bond, it is trans-, B. if on opposite sides, it is trans-, C. Double bonds in naturally occurring unsaturated long-chain fatty acids are nearly all in the trans configuration, the molecules being “bent” 120° at the double bond. D. elaidic acid, is a cis isomer

Answer 45

B. if on opposite sides, it is trans-

Question 46

present in certain foods, arising as a by-product of the saturation of fatty acids during hydrogenation, or “hardening,” of natural oils in the manufacture of margarine.

Answer 46

Trans fatty acids

Question 47

Which is true: A. Consumption of trans fatty acids is not known to be detrimental to health and is associated with increased risk of diseases including cardiovascular disease and diabetes mellitus. B. The melting points of even-numbered carbon fatty acids increase with chain length and decrease according to unsaturation. C. A triacylglycerol containing three saturated fatty acids of 12 or more carbons is liquid at body temperature D. if the fatty acid residues are saturated, it is liquid to below 0°C

Answer 47

B. The melting points of even-numbered carbon fatty acids increase with chain length and decrease according to unsaturation.

Question 48

Which statement is incorrect? A. Long-chain ω3 fatty acids such as α-linolenic (ALA) (found in plant oils), eicosapentaenoic (EPA) (found in fish oil), and docosahexaenoic (DHA) (found in fish and algal oils) have anti-inflammatory effects B. diets rich in ω3 fatty acids are beneficial, particularly for cardiovascular disease, but also for other chronic degenerative diseases such as cancer, rheumatoid arthritis, and Alzheimer disease. C. All of the above D. None of the above

Answer 48

D. None of the above

Question 49

esters of the trihydric alcohol | glycerol and fatty acids

Answer 49

triacylglycerols

Question 50

Many phospholipids are derivatives of __________ in which the phosphate is esterified with one OH group of glycerol and the other two OH groups are esterified to two long-chain fatty acids (glycerophospholipids)

Answer 50

phosphatidic acid

Question 51

important as an intermediate | in the synthesis of triacylglycerols as well as phosphoglycerols but is not found in any great quantity in tissues

Answer 51

phosphatidic acid

Question 52

______ such as sphingomyelin, in which the phosphate is esterified to sphingosine, a complex amino alcohol , are also important membrane components

Answer 52

Sphingolipids

Question 53

Which statement is not true: A. Both glycerophospholipids and sphingolipids have two longchain hydrocarbon tails which are important for their function in forming the lipid bilayer in cell membranes B. Both tail of glycerophospholipid are fatty acid chains C. For spingolipids one is a fatty acid and the second is part of the sphingosine molecule D. All of the above E. None of the above

Answer 53

E. None of the above

Question 54

important in nervous transmission, as | acetylcholine, and as a store of labile methyl groups

Answer 54

Choline

Question 55

This is glycerophospholipids containing choline , are the most abundant phospholipids of the cell membrane and represent a large proportion of the body’s store of choline

Answer 55

(phosphatidylcholines, commonly called lecithins)

Question 56

is a very effective surface-active agent and a major constituent of the surfactant preventing adherence, due to surface tension, of the inner surfaces of the lungs.

Answer 56

Dipalmitoyl lecithin

Question 57

absence of Dipalmitoyl lecithin from the lungs of premature infants causes

Answer 57

respiratory distress syndrome.

Question 58

True or false: Most phospholipids have a saturated acyl radical in the sn-1 position but an unsaturated radical in the sn-2 position of glycerol.

Answer 58

True

Question 59

plays a role in apoptosis (programmed cell death).

Answer 59

Phosphatidylserine

Question 60

minor components of cell membranes, but play an | important part in cell signaling and membrane trafficking.

Answer 60

Phosphorylated phosphatidylinositols | phosphoinositides

Question 61

cleaved into diacylglycerol and inositol trisphosphate upon stimulation by a suitable hormone agonist, and both of these act as internal signals or second messengers.

Answer 61

Phosphatidylinositol 4,5-bisphosphate (PiP2)

Question 62

Is a Major Lipid of Mitochondrial | Membranes

Answer 62

Cardiolipin

Question 63

Phosphatidic acid is a precursor of phosphatidylglycerol, which in turn gives rise to _________

Answer 63

cardiolipin

Question 64

This phospholipid is found only in | mitochondria and is essential for the mitochondrial function

Answer 64

cardiolipin

Question 65

These diseases happen when decreased cardiolipin levels or alterations in its structure or metabolism happens, except: ``` A. mitochondrial dysfunction in aging B. heart failure, C. hypothyroidism D. Barth syndrome (cardioskeletal myopathy). E. All of the above F. None of the above. ```

Answer 65

F. None of the above.

Question 66

These are phosphoacylglycerols containing only one acyl radical, which is important in the metabolism and interconversion of phospholipids

Answer 66

Lysophospholipids

Question 67

This compound is also found in oxidized lipoproteins and has been implicated in some of their effects in promoting atherosclerosis.

Answer 67

Lysophospholipids

Question 68

These compounds constitute as much as 10 to 30% of the phospholipids of brain and heart.

Answer 68

Plasmalogens

Question 69

resemble phosphatidylethanolamine but possess an ether link on the sn-1 carbon instead of the ester link found in acylglycerols.

Answer 69

Plasmalogens

Question 70

True of plasmalogens: A. Typically, the alkyl radical is an unsaturated alcohol B. choline, serine, or inositol may be substituted for ethanolamine. C. The function of plasmalogens remain poorly understood, but it has been suggested that they may have a protective effect against reactive oxygen species. D. All of the above E. None of the above

Answer 70

D. All of the above

Question 71

major glycolipids found in animal tissues are

Answer 71

glycosphingolipids

Question 72

They contain ceramide and one or more sugars

Answer 72

glycosphingolipids

Question 73

is a major glycosphingolipid of brain and other nervous tissue, found in relatively low amounts elsewhere. It contains a number of characteristic C24 fatty acids, for example, cerebronic acid.

Answer 73

Galactosylceramide

Question 74

Galactosylceramide can be converted to sulfogalactosylceramide (sulfatide) which has a sulfo group attached to the O in the three position of galactose and is present in high amounts in _____

Answer 74

myelin

Question 75

resembles galactosylceramide, but the head group is glucose rather than galactose

Answer 75

Glucosylceramide

Question 76

the predominant simple glycosphingolipid of extraneural tissues

Answer 76

Glucosylceramide

Question 77

are complex glycosphingolipids derived from glucosylceramide that contain in addition one or more molecules of a sialic acid

Answer 77

Gangliosides

Question 78

is the principal sialic acid found in human tissues.

Answer 78

Neuraminic acid (NeuAc )

Question 79

They function in cell–cell recognition and communication | and as receptors for hormones and bacterial toxins such as cholera toxin.

Answer 79

Gangliosides

Question 80

The simplest ganglioside found in tissues is _________ which contains ceramide, one molecule of glucose, one molecule of galactose, and one molecule of NeuAc.

Answer 80

GM3

Question 81

a more complex ganglioside derived from GM3, is of considerable biologic interest, as it is known to be the receptor in human intestine for cholera toxin.

Answer 81

GM1

Question 82

What does G M and the subscript means?

Answer 82

G represents ganglioside M is a monosialo-containing species; and the subscript 3 is a number assigned on the basis of chromatographic migration

Question 83

It is the precursor of a large number of equally important steroids that include the bile acids, adrenocortical hormones, sex hormones, vitamin D, and cardiac glycosides

Answer 83

cholesterol

Question 84

All steroids have a similar cyclic nucleus resembling phenanthrene (rings A, B, and C) to which a ____________ is attached

Answer 84

cyclopentane ring (D)

Question 85

Which of the following is not true: A. Each of the six-carbon rings of the steroid nucleus is capable of existing in the three-dimensional conformation either of a “chair” or a “boat” B. In naturally occurring steroids, virtually all the rings are in the “chair” form, which is the more stable conformation. C. the rings can only be cis D. The methyl groups attached to C10 and C13 are invariably in the β configuration. E. All of the above F. None of the above

Answer 85

C With respect to each other, the rings can be either cis or trans

Question 86

Which is true? A. The junction between the A and B rings may be cis or trans in naturally occurring steroids. B. The junction between B and C is trans, as is usually the C/D junction. C. The A ring of a 5α steroid (ie, the hydrogen at position 5 is in the α configuration) is always trans to the B ring, whereas it is cis in a 5β steroid (ie, the hydrogen at position 5 is in the β configuration). D. The methyl groups attached to C10 and C13 are invariably in the β configuration. E. All of the above F. None of the above

Answer 86

E. All of the above

Question 87

is widely distributed in all cells of the body | but particularly in nervous tissue. It is a major constituent of the plasma membrane and of plasma lipoproteins

Answer 87

Cholesterol

Question 88

It is often found as ______________ where the hydroxyl group on position 3 is esterified with a long-chain fatty acid. It occurs in animals but not in plants or bacteria.

Answer 88

cholesteryl ester

Question 89

Is a Precursor of Vitamin D

Answer 89

Ergosterol

Question 90

occurs in plants and yeast and is important as a dietary source of vitamin D

Answer 90

Ergosterol

Question 91

Which is correct? A. When irradiated with ultraviolet light in the skin, ring A is opened to form vitamin D2 B. When irradiated with ultraviolet light in the skin, ring B is opened to form vitamin D2 C. When irradiated with ultraviolet light in the skin, ring C is opened to form vitamin D2 D. All of the above E. None of the aboe

Answer 91

B When irradiated with ultraviolet light in the skin, ring B is opened to form vitamin D2 in a process similar to the one that forms vitamin D3 from 7-dehydrocholesterol in the skin

Question 92

are not steroids but are related to them because they are synthesized, like cholesterol from five-carbon isoprene units

Answer 92

Polyprenoids

Question 93

The process in which exposed to oxygen is responsible not only for deterioration of foods (rancidity), but also for damage to tissues in vivo, where it may be a cause of cancer, inflammatory diseases, atherosclerosis, and aging.

Answer 93

Peroxidation (auto-oxidation) of lipids

Question 94

molecules that have unpaired valence electrons, | making them highly reactive.

Answer 94

free radicals

Question 95

Free radicals containing oxygen (eg, ROO•, | RO•, OH•) are termed

Answer 95

reactive oxygen species (ROS).

Question 96

produced during peroxide formation from fatty acids containing methylene-interrupted double bonds, that is, those found in the naturally occurring polyunsaturated fatty acids

Answer 96

reactive oxygen species (ROS).

Question 97

is a chain reaction in which free radicals formed in the initiation stage in turn generate more (propagation), and thus it has potentially devastating effects.

Answer 97

Lipid peroxidation

Question 98

only formed by fatty acids with three or more double bonds and is used as a measure of lipid peroxidation together with ethane from the terminal two carbons of ω3 fatty acids and pentane from the terminal five carbons of ω6 fatty acids.

Answer 98

Malondialdehyde

Question 99

correct sequence of lipid peroxidation:

Answer 99

initiation, propagation, termination

Question 100

are used to control and reduce lipid peroxidation, both by humans in their activities and in nature.

Answer 100

Antioxidants

Question 101

All are antioxidant except: ``` A. Propyl gallate B. butylated hydroxyanisole (BHA) C. butylated hydroxytoluene (BHT) D. Tocopherol E. All of the above F. None of the above ```

Answer 101

F. None of the above

Question 102

True of antioxidant except: A. vitamin E (tocopherol) is lipid soluble, B. vitamin E (tocopherol) is water soluble soluble, C. vitamin C is water soluble D. urate is water soluble E. All of the above F. None of the above

Answer 102

B. because: vitamin E (tocopherol) is lipid soluble,

Question 103

Antioxidants fall into two classes:

Answer 103

preventive and chain-breaking antioxidants,

Question 104

which reduce the rate of chain initiation

Answer 104

preventive | antioxidants

Question 105

interfere with chain propagation

Answer 105

chain-breaking antioxidants,

Question 106

True of Preventive antioxidants: A. include catalase B. glutathione peroxidase that react with ROOH C. In vivo, the principal chain-breaking antioxidants are superoxide dismutase, which acts in the aqueous phase to trap superoxide free radicals D. All of the above E. None of the above

Answer 106

D. All of the above

Question 107

True of peroxidation: A. Peroxidation is also catalyzed in vivo by heme compounds and by lipoxygenases found in platelets and leukocytes. B. Other products of auto-oxidation or enzymic oxidation of physiologic significance include oxysterols (formed from cholesterol) and the prostaglandin-like isoprostanes (formed from the peroxidation of polyunsaturated fatty acids such as arachidonic acid) which are used as reliable markers of oxidative stress in humans. C. All of the above D. None of the above

Answer 107

C. All of the above

Question 108

are used as reliable markers of oxidative stress in humans.

Answer 108

isoprostanes (formed from the peroxidation of | polyunsaturated fatty acids such as arachidonic acid)

Question 109

True of lipids: A. lipids are insoluble in water since they contain a predominance of nonpolar (hydrocarbon) groups B. fatty acids, phospholipids, sphingolipids, bile salts, and, to a lesser extent, cholesterol contain polar groups. C. a part of the molecule is hydrophobic, or water insoluble, and a part is hydrophilic, or water soluble. Such molecules are described as amphipathic D. A bilayer of such amphipathic lipids is the basic structure in biologic membranes E. All of the above F. None of the above

Answer 109

E. All of the above

Question 110

When a critical concentration of these lipids is present in an aqueous medium, they form

Answer 110

micelles

Question 111

may be formed by sonicating an amphipathic lipid in | an aqueous medium.

Answer 111

Liposomes

Question 112

are much larger particles, formed usually by nonpolar lipids in an aqueous medium.

Answer 112

Emulsions