Midterms Quizzes Flashcards by Lili Popp

Which of the following tests will confirm the presence of starch?
a. Molisch’s Test
b. Lugol’s Test
c. Seliwanoff’s Test
d. Benedict’s Test

Lugol’s Test

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Which of the following tests will NOT produce a precipitate?
a. Fehling’s Test
b. Lugol’s test
c. Barfoed’s Test
d. Bial’s test

Lugol’s test

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T or F
Libermann-Burchard test is used to determine the presence of lipids.

FASLE
Libermann-Burchard test is used to determine the presence of Cholesterol.

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T or F
The ether increases the catalyst solubility between the base compound and the fat in the saponification process.

FALSE
The ethanol increases the catalyst solubility between the base compound and the fat in the saponification process.

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Which of the following is the role of liquid detergent in the Sudan dye test?
a. reducing agent
b. hydrating agent
c. emulsifier
d. dehydrating agent

emulsifier

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Which of the following reagents does NOT contain copper?
a. Tollen’s reagent
b. Benedict’s reagent
c. Fehling’s reagent
d. Barfoed’s reagen

Tollen’s reagent

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Which of the following is the negative confirmatory result for Bial’s test?
a. olive green precipitate
b. blue color solution
c. brick red precipitate
d. faint pink color solution

Olive green precipitate

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Which of the following components of the Molisch test dehydrates the sugar molecule?
a. sulfuric acid
b. a-naphthol
c. resorcinol
d. orcinol

sulfuric acid

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T or F
Soaps form solid deposits when added to hard water containing Mg+2 and Ca+2.

TRUE

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An unknown sample was subjected to miscibility test. It formed two layers with water and a homogenous mixture with acetone. What can be inferred with this observation?

The sample is nonpolar because it did not mix with water.

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The following samples may give a positive result with Fehling’s test EXCEPT:
a. Galactose
b. Sucrose
c. Lactose
d. Maltose

Sucrose

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Which of the following tests will confirm the presence of monosaccharide or disaccharide?
a. Benedict’s Test
b. Seliwanoff’s Test
c. Bial’s Test
d. Barfoed’s Test

Barfoed’s Test

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Which of the following tests will confirm the presence of disaccharide after a prolonged observation?

a.
Molisch’s Test

b.
Benedict’s Test

c.
Barfoed’s Test

d.
Lugol’s Test

Barfoed’s Test

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Honey is an example of ?

Carbohydrate

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T or F
Glucose will react positively to Tollen’s test.

TRUE

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Which of the following samples will give a positive result to Seliwanoff’s test?

a.
Bread solution

b.
Sucrose

c.
Ribose

d.
Lactose

Sucrose

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Which of the following tests will confirm the presence of reducing sugar?

a.
Molisch’s Test

b.
Seliwanoff’s Test

c.
Lugol’s Test

d.
Fehling’s Test

Fehling’s Test

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Which of the following is the reaction of bromine molecules in the structure of lipids?

a.
It decreases the degree of unsaturation by adding itself on each side of the double bond.

b.
It increases the degree of unsaturation by removing hydrogen atoms in the structure.

c.
It breaks the double bond which makes a red-orange solution.

d.
It decolorizes the solution due to the presence of saturated bonds in the structure of lipids.

It decreases the degree of unsaturation by adding itself on each side of the double bond.

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Why is NaOH used for the saponification process?

a.
to hydrolyze the soap and covert it to free fatty acids

b.
to dehydrate the fat and convert it to a salt

c.
to neutralize the free fatty acids that yield salt

d.
to emulsify the triglycerides with glycerol and produce a fatty acid salt

to neutralize the free fatty acids that yield salt

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Which of the following tests for lipids will produce a precipitate as a positive result?

a.
Sudan Dye Test

b.
Liebermann-Burchard test

c.
Copper acetate test

d.
Bromine test

Copper acetate test

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Which of the following is the positive reaction of the Copper sulfate test for lipids?

a.
appearance of two layers containing the dense bluish solution

b.
formation of light pink precipitate

c.
appearance of dark green solution

d.
formation of the copper salts

formation of the copper salts

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Which of the following statements is true about Barfoed’s test?

a.
Barfoed’s test is used to determine the presence of nonreducing sugar under basic condition.

b.
Barfoed’s test is used to determine the presence of reducing sugar under acidic condition.

c.
Barfoed’s test is used to determine the presence of reducing sugar under basic condition.

d.
Barfoed’s test is used to determine the presence of nonreducing sugar under acidic condition.

Barfoed’s test is used to determine the presence of reducing sugar under acidic condition.

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T or F
A sphingophospholipid has a phosphate ion, phosphatidyl ester, and one fatty acid attached in the amino group of the sphingosine structure.

TRUE

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Which of the following is the effect of the metal ions on soap solution? a. decreases the hardness of the soap solution b. decreases the foam level of the soap solution c. formation of soluble salts d. increases the cleansing property of the soap

Decreases the foam level of the soap solution

Which of the following substances will test positive to Sudan III Dye Test? a. palm oil b. Water c. Salt solution d. Sugar solutionWhich of the following substances will test positive to Sudan III Dye Test? a. palm oil b. Water c. Salt solution d. Sugar solution

palm oil

T or F Bromine test will confirm the presence of saturated fatty acids.

FALSE Bromine test will confirm the presence of unsaturated fatty acids.

A lipid is any substance of biochemical origin that is ? 9sulubility)

insoluble in both water and nonpolar solvents

Which of the following is important for brain development? a. a-tocopherol b. arachidonic acid c. docosahexaenoic acid d. linoleic acid

docosahexaenoic acid

Fats and oils are structurally both triacylglycerols, but fats are solids at room temperature and oils are liquids at room temperature. Which statement best describes the reason for their difference in physical state?

Fats contain a higher percentage of saturated fatty acids than oils do, and therefore have higher melting points than oils.

Which of the following types of lipids is a steroid? a. leukotrienes b. thromboxanes c. androgens d. prostaglandins

androgens

Which of the following fatty acids has the lowest melting point? a. CH3(CH2)4(CH=CHCH2)4(CH2)2COOH b. CH3(CH2)18COOH c. CH3(CH2)7CH=CH(CH2)7COOH d. CH3(CH2)5CH=CH(CH2)7COOH

CH3(CH2)4(CH=CHCH2)4(CH2)2COOH

Which statement is NOT true about cholesterol? a. Cholesterol serves as the starting material for the synthesis of all other steroids. b. Cholesterol is a vital component for healthy cell membranes. c. Cholesterol is the most prominent member of the steroid family. d. Cholesterol cannot be synthesized in the body, and therefore is required in the diet.Cholesterol cannot be synthesized in the body, and therefore is required in the diet.

Cholesterol cannot be synthesized in the body, and therefore is required in the diet.

In which of the following types of lipids have one amide linkage present?

glycolipids

T or F The saponification process of triglycerides yields the by-products of water and fatty acid salts.

FALSE

Which structural feature is not found in sphingomyelins? A phosphodiester b. An amide bond c. An alcohol d. A glycerol backbone

A glycerol backbone

Biological waxes are formed from the reaction between which two types of compounds? a. A fatty acid and an amide b. An ester and a fatty acid c. A high molecular weight alcohol and an ester d. A fatty acid and a high molecular weight alcohol

A fatty acid and a high molecular weight alcohol

Which is NOT true about prostaglandins? a. Prostaglandins decrease inflammation. b. Prostaglandins inhibit blood platelet aggregation. c. Prostaglandins stimulate uterine contractions. d. Prostaglandins decrease gastric secretions.

rostaglandins decrease inflammation.

T or F The coating that surrounds and insulates nerve cells, the myelin sheath, is particularly rich in ceramide, and is vital for proper nerve function.

FASLE

T or F A phospholipid cephalin helps in blood clotting and also named as phosphatidylcholine.

FALSE

T or F In a plasma membrane, the active transport is driven by the chemical energy adenosine triphosphate with the help of protein receptors.

TRUE

Which of the following vitamins is responsible for bone development? a. a-tocopherol b. cholecalciferol c. menaquinone d. retinol

cholecalciferol

T or F The melting and boiling point of lipids depends on the length of the carbon chain and no. of saturated fatty acids in the structure.

FASLE

hich of the following fatty acids is both monounsaturated and an omega-6 fatty acid? a. CH3–(CH2)18–COOH b. CH3–(CH2)4–CH=CH–(CH2)2–(CH2)6–COOH c. CH3–(CH2)7–CH=CH–(CH2)7–COOH d. CH3–CH2–(CH=CH–CH2)4–(CH2)2–COOH

CH3–(CH2)4–CH=CH–(CH2)2–(CH2)6–COOH

The following over-the-counter drugs may inhibit the COX1 to produce prostaglandin (PGE2) in the body EXCEPT: a. Naproxen b. Paracetamol c. Aspirin d. Ibuprofen

Paracetamol

Which of the following statements concerning fats and oils is incorrect? a. They are glycerol triesters. b. They are use to make fatty acid salts. c. They are also called triglycerides. d. They are also called triacylglycerols.

They are glycerol triesters.

Which of the following statements concerning fatty acids is incorrect? a. At least 16 carbon atoms must be present in the carbon chain of a fatty acid. b. Fatty acids are rarely found in the free state in nature. c. Double bonds present in fatty acids are almost always in a cis-configuration. d. Some fatty acids needed in the human body must be obtained from food because they cannot be synthesized with the body.

At least 16 carbon atoms must be present in the carbon chain of a fatty acid.

The following shows the effect of NSAIDs (non-steroidal anti-inflammatory drugs) in the body EXCEPT: a. It lowers the body temperature b. It increases the secretion of protective mucus layer in stomach c. It relieves the pain and fever d. It allows secretion of gastric juices in stomach

It increases the secretion of protective mucus layer in stomach

T or F Soap is prepared by the acid hydrolysis (saponification) of a triacylglycerol.

False

Which of the following statements concerning the molecule sphingosine is correct? a. Two amino groups and one hydroxyl group are present. b. Its carbon chain contains 20 carbon atoms. c. Its carbon chain is saturated. d. One amino group and two hydroxyl groups are present.

One amino group and two hydroxyl groups are present.

Which of the following is TRUE about the visual cycle in rod cells of the eyes? a. cis-retinol undergo isomerization to change in trans-retinol b. cis-retinal binds to opsin and produce a visual pigment c. cis-retinal develops a visual pigment with the help of opsin d. cis-retinal forms a visual pigment called opsin

cis-retinal binds to opsin and produce a visual pigment

Which type of fatty acid is most common in olive oil?

Monounsaturated

T or F Cholesterol, bile acids, and eicosanoids are considered nonsaponifiable lipids due to the non-existence of the ester, amide, and glycosidic linkages.

TRUE

Why is cholesterol important in a plasma membrane?

It holds the phospholipid tails to regulate membrane transport.

RT or F Trans double bonds can be formed when triacylglycerols are partially hydrogenated.

TRUE

Which of the following statements concerning carbohydrates is correct? A. They all have a sweet taste and therefore are also called sugars. B. They are the most abundant type of biochemical substance in the human body. C. They are all polyhydroxy aldehydes, polyhydroxyketones, or substances that yield such upon hydrolysis. D. They can exist in left-handed and right-handed forms, with the left-handed form being dominant in nature

C. They are all polyhydroxy aldehydes, polyhydroxyketones, or substances that yield such upon hydrolysis.

Which of the following terms correctly describes the relationship between D-fructose and Lfructose? A. enantiomers C. diastereomers B. epimers D. stereoisomers

A. enantiomers

What monosaccharide is found in cellulose, starch, and glycogen?

A. Glucose

What is the polysaccharide form in which glucose is stored in animals?

D. Glycogen

. Which is NOT a reducing sugar? A. Glucose B. Fructose C. Sucrose D. Galactose

Sucrose

In which of the following pairs or carbohydrates are both members of the pair disaccharides? A. allose and idose C. lactose and arabinose B. sucrose and maltose D. cellobiose and cellulose

B. sucrose and maltose

The major structural difference between cellulose and starch is found in the

linkages between the monosaccharide units present

Which carbohydrates cannot be converted to simpler compounds by hydrolysis? A. Disaccharides B. Monosaccharides C. Polysaccharides D. Starches

Monosaccharides

MonosaccharidesWhat are monosaccharides with a carbonyl group at C1 called? A. Anomers B. Aldoses C. Ketoses D. Alditols

Aldoses

In which of the following polysaccharides are all glycosidic linkages of the β (1→ 4) type? A. starch B. glycogen C. cellulose D. amylopectin

cellulose

Disaccharides and polysaccharides contain monosaccharide units joined together by which of the following? A. Hydrogen bonding C. Glycosidic linkages B. Hemiacetal bonds D. Dipole-dipole forces

Glycosidic linkages

Which of the following substances will produce both glucose and fructose when hydrolyzed? A. lactose B. maltose C. sucrose D. glycogen

sucrose

. In which of the following disaccharides is a β (1→4) glycosidic linkage present? A. lactose B. maltose C. sucrose D. none of the choices

lactose

Which of the following is the simplest ketotriose? A. glyceraldehyde B. dihydroxyacetone. C. ribose D. glucose

. dihydroxyacetone

. A component of glycosaminoglycans that is responsible for repairing damaged cartilage in connective tissues.

Hyaluronic Acid

. A pyranose is a sugar that _

contains a six-membered ring as part of its cyclic structure.

For the α- anomer of a D-sugar, the anomeric hydroxyl in a Haworth projection: A. has an upward projection (on the same side as the terminal CH2OH group). B. has a downward projection (on the opposite side from the terminal CH2OH group). C. may be either up or down, it depends on the individual sugar. D. is non-existent; anomers are a consideration only in Fischer projections.

. has a downward projection (on the opposite side from the terminal CH2OH group).

Which of the following substances will produce 2 units of D-glucose when hydrolyzed? A. lactose B. maltose C. sucrose D. glycogen

Maltose

Which of the following is considered an aldotriose? A. acetone B. dihydroxyacetone C. glyceraldehyde D. d-ribose

glyceraldehyde

. A furanose is a sugar that _

contains a five-membered ring as part of its cyclic structure

Which of the following is NOT a function of carbohydrates? A. They are major energy sources. B. They are used in structural roles. C. They are catalytic components of enzymes.

They are catalytic components of enzymes.

In which of the following pairs of carbohydrates are both members of the pair polysaccharides? A. cellulose and cellobiose C. starch and glycogen B. amylose and lactose D. None of the choices

starch and glycogen

The Haworth projection formulas _________. A. are representations of the cyclic form of sugars B. can show the distinction between the α and β anomers. C. both of the above D. neither of the above

both of the above

Aldoses can form which type of cyclic sugar structure?

Hemiacetal

The difference between cellobiose and maltose is: A. one contains glucose and the other fructose B. they contain different monosaccharides C. one has an α linkage and the other a β linkage

one has an α linkage and the other a β linkage

. Which of the following statements associated with cellulose is FALSE? A. It's a linear polymer of glucose. B. The glycosidic linkage is β-(1→4). C. Hydrolysis is accomplished enzymatically by cellulase. D. Most animals can easily digest this compound.

Most animals can easily digest this compound.

It is the enantiomer of D-glucose A. D-Fructose B. L-Glucose C. D-Glucose D. L-Idose

L-Glucose

Glycogen is ___________. A. a linear polysaccharide B. a synthetic sugar substitute C. polysaccharide storage polymer found in plants D. a highly branched polysaccharide found in animals

a highly branched polysaccharide found in animals

. The diastereoisomers of D-Glucose include all of these, except: A. D-Fructose B. L-Idose C. L-Glucose D. D-Galactose

L-Glucose

. Humans are not able to digest cellulose as a food source because: A. Cellulose is very insoluble. B. It is more important that cellulose is used as fiber in our bodies. C. We lack the enzyme to break the α linkage in the cellulose. D. Cellulose is insoluble and we lack the enzyme to break the β linkage in the cellulose.

Cellulose is insoluble and we lack the enzyme to break the β linkage in the cellulose.

. Chitin, which forms the exoskeletons of insects, is composed of: A. α(1→4) linked glucose residues B. β(1→4) linked glucose residues C. α(1→4) linked N-acetylglucosamine residues D. β(1→4) linked N-acetylglucosamine residues

β(1→4) linked N-acetylglucosamine residues

ABO Blood typing depends on

the nature of the oligosaccharide portion of glycoproteins on the surface of red blood cells

Which of the following has an α [1→ 4] linkages and a branched α [1→ 6] linkages? A. Glycogen B. Amylose C. Amylopectin D. Cellulose

Amylopectin

Which of the following is TRUE about the ABO blood groups? A. type AB blood is the universal donor B. type B blood has a β-N-acetylgalactosamine group C. all three of the blood groups have an α-L-fucose group attached

. all three of the blood groups have an α-L-fucose group attached

. What is the difference between the disaccharides lactose and maltose? A. Lactose can be hydrolyzed in the body, but maltose cannot. B. Lactose contains both an acetal and a hemiacetal, while maltose contains two acetals. C. Lactose contains two glucose units, while maltose contains two galactose units. D. The two monosaccharides in lactose are joined by a 1→4-β-glycoside bond, while the two monosaccharides in maltose are joined by a 1→4-α-glycoside bond.

The two monosaccharides in lactose are joined by a 1→4-β-glycoside bond, while the two monosaccharides in maltose are joined by a 1→4-α-glycoside bond.

Midterms Quizzes Flashcards

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