Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biomolecules > MCQ Practice Questions > Flashcards

MCQ Practice Questions Flashcards

1
Q

The use of water to break a chemical bond is referred to as ______

a) dehydrogenation
b) hydrolysis
c) dehydration
d) hydration
e) hydrogenation

A

Hydrolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which atom does NOT commonly form hydrogen bonds between or within biological molecules?

a) Nitrogen
b) Hydrogen
c) Carbon
d) Oxygen
e) All four form hydrogen bonds

A

Carbon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which statement about hydrogen is FALSE?

a) They cause acid-base reactions in aqueous solutions to be very rapid
b) They are weak compared with covalent bonds
c) They have an optimal geometry
d) They only occur at neutral pH
e) They only occur between water molecules

A

e) They only occur between water molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which weak acid would be best to use when preparing a buffer solution with a pH of 7.7?

a) An acid with Ka = 3.2 x 10^-7
b) An acid with Ka = 2.5 x 10^-5
c) An acid with Ka = 2.5 x 10^-8
d) An acid with Ka = 1.0 x 10^-11
b) An acid with Ka = 1.7 x 10^-10

A

c) An acid with Ka = 2.5 x 10^-8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many optical isomers does threonine have?

a) 2
b) 4
c) 3
d) 1
e) 5

A

b) 4
Because threonine has 2 chiral carbons
(2^n where n = no. of chiral carbons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the name and 3-letter abbreviation of the amino acid G?

a) Glycine and Glu
b) Glutamate and Glu
c) Glycine and Gly
d) Glutamic acid and Glu
e) Glutamine and Glu

A

c) Glycine and Gly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which of the following statements about peptide bonds are TRUE?

a) Peptide bond formation is a hydrolysis reaction
b) Peptides are polymers of proteins
c) Peptide bonds are amide linkages
d) A tetrapeptide contains three amino acid residues
e) Peptide bonds form from nucleophillic attack by an alpha-carboxyl carbon atom

A

c) Peptide bonds are amided linkages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Leucine is best classed as _____

a) non-polar
b) negatively charged
c) positively charged
d) polar
e) aromatic

A

a) non-polar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the HIGHEST level of protein structure in haemoglobin?

a) Tertiary
b) Primary
c) Quaternary
d) Diva
e) Secondary

A

c) Quaternary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Glyceraldehyde has how many chiral carbons?

a) 3
b) 2
c) 1
d) 4
e) none

A

c) 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What chemical feature determines if a sugar is an aldose or a ketose?

a) The number of chiral carbons
b) If the epimers differ in configuration around one carbon or more than one carbon
c) The direction of rotation of polarized light
d) The position of the carbonyl carbon
e) If the enantiomers resemble either glyceraldehyde or dihydroxyacetone

A

d) The position of the carbonyl carbon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which one of the following is not glycoconjugate?

a) Syndecans
b) Glypicans
c) N-linked glycan
d) Trehalose
e) Glycosphingolipids

A

d) Trehalose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the name given to monosaccharides that differ in configuaration about the hemiacetal carbon atom?

a) Epimers
b) Glycosides
c) Isomers
d) Anomers
e) Enantiomers

A

d) Anomers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which O-glycosidic bond is commonly found in amylose, amylopectin, and glycogen?

a) (alpha 1-4)
b) (beta 1-4)
c) (alpha 1-6)
d) (beta 1-6)
e) (alpha 1-3)

A

a) (alpha 1-4)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What name is given to carbohydrates linked by their anomeric carbons?

a) hemiketals
b) non-reducing sugars
c) glycans
d) anomers
e) glycosides

A

b) non-reducing sugars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Glycogen is a polymer of which one of the following?

a) lactose
b) galactose
c) fructose
d) glucose
e) sucrose

A

d) glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Bond dissociation energy is the:

a) kinetic energy of motion of individual atoms and molecules
b) energy required to form hydrogen bonds
c) energy required to break a bond
d) ability of one atom to attract the most electrons in a molecule
e) energy required to form covalent bonds

A

c) energy required to break a bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

H2CO3 –> HCO3- + H+

Which is the acid in this conjugate acid-base pair?

a) H2CO3
b) HCO3-
c) H+
d) there is no acid in the equation

A

a) H2CO3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which equation is the Henderson-Hasselbach equation?

a) F = Q1 x Q2 / εr^2
b) pH = pKa
c) pH = -log[H+]
d) pH = pKa + log [A-] / [HA]

A

d) pH = pKa + log [A-] / [HA]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which is the greater thermodynamic contributor to the spontaneous evapouration of a liquid?

a) the endergonic nature of the evapouration process
b) the entropy change
c) the enthalpy change
d) either the entropy or enthalpy change, depending on the substance

A

b) the entropy change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which statement is false regarding the accurate determination of pH?

a) comparison of the test solution to reference standards is necessary
b) the electrode should be glass
c) the electrode directly meausures the hydrogen ion concentration of the test solution
d) the electrode should be insensitive to cations such as Na+ and K+

A

c) the electrode directly meausures the hydrogen ion concentration of the test solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Identify the type of lipid shown

a) Steroid
b) Wax
c) Phospholipid
d) Fatty Acid
e) Triacylglycerol

A

e) Triacylglycerol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which of the following statements regarding linoleic acid (18:2(Δ9,12)) is true?

a) It has two caroxylic acid functional groups
b) It has a C-C double bond between carbons 9 and 10
c) It has 20 carbons
d) It has one double bond
e) It has 18 double bonds

A

b) It has a C-C double bond between carbons 9 and 10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which of the following is generally not found in membrane lipids?

a) Glycerophospholipids
b) Glycolipids
c) Triacylglycerols (Triglycerides)
d) Cholesterol
e) Sphingolipids

A

c) Triacylglycerols (Triglycerides)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

For fatty acids with the same number of carbon atoms, how does the melting point change as the number of double bonds in the fatty acid changes?

a) The melting point of the fatty acid is unchanged as the number of double bonds changes
b) There is no relationships between the melting point of a fatty acid and the number of double bonds
c) The melting point of the fatty acid decreases as the number of double bonds decreases
d) The melting point of the fatty acid decreases as the number of double bonds increases
e) The melting point of the fatty acid increases as the number of double bonds increases

A

d) The melting point of the fatty acid decreases as the number of double bonds increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which carbon in the pentose sugar forms a glycosidic bond with the nitrogenous base in a nucleoside?

a) C-1
b) C-5’
c) C-1’
d) C-2’
e) C-3’

A

c) C-1’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which of the following statements describes purines and pyrimidines in DNA molecules?

a) Purines form hydrogen bonds with purines
b) Pyrimidines form covalent bonds with purines
c) Pyrimidines form hydrogen bonds with purines
d) Pyrimidines consist of a one-ring structure
e) Adenine and guanine are pyrimidines

A

c) Pyrimidines form hydrogen bonds with purines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which one of the following statements about the structure of the DNA double helix is true?

a) The nitrogenous bases are on the inside of the double helix because they are hydrophobic and do not interact with the aqueous envrionment surrounding the DNA
b) The nitrogenous bases are on the outside of the double helix because they are hydrophobic and interact with the aqueous envrionment surrounding the DNA
c) The phosphate groups are on the outside of the double helix because they are charged and interact with the aqueous envrionment surrounding the DNA
d) The phosphate groups are on the inside of the double helix because they are non-polar and do not interact with the aqueous envrionment surrounding the DNA
e) All are incorrect

A

c) The phosphate groups are on the outside of the double helix because they are charged and interact with the aqueous envrionment surrounding the DNA

29
Q

Classify the following nucleotide or nucleoside by the type of base and sugar groups present

a) Purine and ribose
b) Pyrimidine and deoxyribose
c) Purine and deoxyribose
d) Pyrimidine and ribose

A

d) Pyrimidine and ribose

30
Q

Which tertiary DNA structure has more nucleotide pairs per turn of DNA?

a) A-DNA
b) Left-handed DNA
c) Z-DNA
d) Right-handed DNA
e) B-DNA

A

c) Z-DNA

31
Q

Consider the four structures. Which one of the following are correct?

a) C = Guanine and D = Adenine
b) A = Cytosine and B = Thymine
c) A = Thymine and B = Cytosine
d) C = Adenine and D =Thymine
e) B = Adenine and D = Guanine

A

c) A = Thymine and B = Cytosine

32
Q

Carbohydrates, or saccharides, are classified into three main types according to their structure: monosaccharides, disaccharides and polysaccharides. Which one of the following represents a pair of polysaccharides?

a) Sucrose and Galactose
b) Cellulose and Lactose
c) Glycogen and Cellulose
d) Lactose and Sucrose
e) Glucose and Glycogen

A

c) Glycogen and Cellulose

33
Q

Analyse the following pairs of compounds and select the term that best explains the relationship between each of the pairs of compounds

a) Diastereomers
b) Anomers
c) Synomers
d) Enantiomers
e) Epimers

A

d) Enantiomers

34
Q

Proteoglycans are composed of proteins conjugated to carbohydrate components called glycosaminoglycans, which are part of the extracellular matrix and provide structure, viscosity, adhesiveness and lubrication. Which one of the following statements about glycosaminoglycans is true?

a) Dextran is an example of a glycosaminoglycan
b) Glycosaminoglycans are homopolysaccharides composed of repeating glucosamine or galactosamine residues
c) Because glycosaminoglycans consist of only two residues, they generally are very small and have low molecular weights.
d) Glycosaminoglycans are heteropolysaccharides composed of repeating disaccharide units
e) Amylose is a possible component of glycosaminoglycans

A

d) Glycosaminoglycans are heteropolysaccharides composed of repeating disaccharide units

35
Q

Which one of the following best describes glycoproteins?

a) They always contain a lipid component
b) They contain unbranched oligosaccharides
c) They have oligosaccharides covalently attached to aspartate residues.
d) They represent many of the cell surface or extracellular proteins
e) They are a very small fraction of the total number of proteins in a human cell

A

d) They represent many of the cell surface or extracellular proteins

36
Q

Which one of the following best describes a monosaccharide with a ketone functional group and seven carbons?

a) It does not exist under normal biological conditions
b) It can never exist in a cyclic form
c) It has a single chrial centre
d) It is the monosaccharide found in RNA but not in DNA
e) It is a ketoheptose

A

e) It is a ketoheptose

37
Q

Regarding the cyclisation of monosaccharides, which one of the following is true?

a) It creates α and β epimers
b) Under normal biological conditions cyclic or linear monosaccharides are more abundant than cyclical monosaccharides
c) It only occurs in hexoses
d) It is an irreversible reaction
e) It is a reaction which forms hemiketals or hemiacetals

A

e) It is a reaction which forms hemiketals or hemiacetals

38
Q

The reaction below is catalyzed by the enzyme aminopeptidase. Determine whether aminopeptidase shows absolute specificity, stereochemical specificity, group specificity or linkage specificity.

a) No specificity
b) Absolute specificity
c) Group specificity
d) Stereochemical specificity
e) Linkage specificity

A

c) Group specificity

39
Q

A variety of factors influence enzyme activity. Which one of the following best describes the characteristics of a non-competitive inhibitor?

a) Binding of the inhibitor increases Km but not Vmax
b) Non-competitive inhibitors may permanently modify an enzyme
c) Transition state analogue inhibitors are an example of non-competitive inhibitors
d) Binding of the inhibitor increases both Km and Vmax
e) Binding of the inhibitor increases Km but decreases Vmax

A

e) Binding of the inhibitor increases Km but decreases Vmax

40
Q

The Lineweaver-Burk plot, is a graphical representation of enzyme kinetics that is typically used to determine the maximum rate (Vmax) and the Michalis constant (Km), which can be obtained from the intercepts and slope of the line. Identify each intercept in terms of the constants Vmax and Km in the graph below.

a) A = -1/Km B = 1/Vmax
b) A = 1/Km B = 1/Vmax
c) A = Km B = Vmax
d) A = Vmax B = Km
e) A = 1/Vmax B = -1/Km

A

a) A = -1/Km B = 1/Vmax

41
Q

Which category does the enzyme that catalyses the following reaction belong to?

a) Transferase
b) Lyase
c) Isomerase
d) Oxidoreductase
e) Hydrolase

A

c) Isomerase

42
Q

Which one of the following aspects of an enzyme catalysed reaction is correct?

a) Addition of enzyme decreases the rate of the reverse reaction
b) Addition of an enzyme reduces the temperature of the solution
c) Addition of enzyme increases the activation energy of the forward reaction
d) Addition of enzyme increases the rate of the forward reaction
e) Addition of enzyme increases the activation energy of the reverse reaction

A

d) Addition of enzyme increases the rate of the forward reaction

43
Q

Increasing substrate concentration restores enzyme activity that has been blocked by which one of the following?

a) Neither a competitive nor a non-competitive inhibitor
b) An irreversible inhibitor only
c) A competitive inhibitor only
d) Both a competitive and a non-competitive inhibitor
e) A non-competitive inhibitor only

A

c) A competitive inhibitor only

44
Q

A buffer solution contains a weak acid [HA] and its conjugate base [A-]. The buffer solution has a pH of 5.58 and has a pKa of 5.29. Without performing a calculation, determine the relationship between the concentration of the weak acid and the concentration of the conjugate base in this buffer solution?

a) [HA] > [A-]
b) The relationship between [HA] and [A-] cannot be determined
c) None are correct
d) [HA] < [A-]
e) [HA] = [A-]

A

d) [HA] < [A-]

45
Q

Peptide bonds are Ionic and can rotate freely

TRUE or FALSE?

A

FALSE
Peptide bonds are Covalent and Planar

46
Q

Why is rotation of the peptide bond limited?

A

There is resonance about the C-N bond giving it some partial double bond properties

47
Q

What are the functions of chaperone proteins?

A

Prevent misfolding and aggregation of unfolded peptides

48
Q

The peptide bond is Polar

TRUE or FALSE?

A

TRUE
The oxygen and nitrogen have parallel negative and positive charges respectively

49
Q

What kind of sequence give an α-helix with one hydrophobic face?

A

Amphipathic

50
Q

β pleated sheets are an example of what form of protein structure?

a) Diva
b) Quaternary
c) Primary
d) Tertiary
e) Secondary

A

e) Secondary

α helices and β pleated sheets are the two secondary structures

51
Q

A β barrel is an example of what form of protein structure?

a) Diva
b) Quaternary
c) Primary
d) Tertiary
e) Secondary

A

d) Tertiary

52
Q

How many chiral carbons are in Glucose?

A

4

53
Q

Which of the following structures is a 20:2(Δ4, 9) fatty acid?

a) CH3(CH2)10CH = CH(CH2)3CH = CHCH2COOH
b) CH3CH2CH = CH(CH2)3CH = CH(CH2)10COOH
c) CH3(CH2)9CH = CH(CH2)3CH = CH(CH2)2COOH
d) CH3CH2CH = CH(CH2)2CH = CH(CH2)10COOH
e) CH3(CH2)2CH = CH(CH2)3CH = CH(CH2)9COOH

A

c) CH3(CH2)9CH = CH(CH2)3CH = CH(CH2)2COOH

Carbon count = 20
2 double bonds
Bonds occur after C4 and C9

If Δ then count from COOH (Carboxyl End)

54
Q

Phosphatidylcholine is an example of which of the following?

a) Ether lipid
b) Polysaccharide
c) Phospholipid
d) Sphingolipid
e) All are correct

A

c) Phospholipid

55
Q

What is the Michaelis-Menten equation?

A
56
Q

What Nitrogeous Base is this?

A

Adenine
(Purine)

57
Q

What Nitrogeous Base is this?

A

Guanine
(Purine)

58
Q

What Nitrogeous Base is this?

A

Cytosine
(Pyrimidine)

59
Q

What Nitrogeous Base is this?

A

Thymine
(Pyrimidine)

60
Q

What Nitrogeous Base is this?

A

Uracil
(Pyrimidine)

61
Q

What are the THREE main Monosaccharides in nutrition?

A

Glucose, Fructose, Galactose

62
Q

Glucose + Glucose =

A

Maltose

63
Q

Glucsose + Fructose =

A

Sucrose

64
Q

Glucose + Galactose =

A

Lactose

65
Q

How does a COMPETITIVE inhibitor affect Vmax and Km?

A

Vmax stays the same
Km increases

66
Q

How does a NON-COMPETITIVE inhibitor affect Vmax and Km?

A

Km stays the same
Vmax decreases

67
Q

How does an UNCOMPETITIVE inhibitor affect Vmax and Km?

A

Km decreases
Vmax decreases

68
Q

What are the Polar (Hydrophilic) amino acids?

A

Cysteine, Serine, Threonine, Asparagine, Glutamine, Aspartic Acid, Glutamic Acid, Histidine, Arginine, Lysine

CSTAG, Acids, Basic HARLY

Biomolecules (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions