T1 | Test 1 Chap. 1-5 Flashcards

1
Q

What is include in the basic structure of an alpha-Amino Acid (4)

A
  • Amino group: protonated at the physiological pH (H3N+)
  • Carboxyl group (organic acid): deprotonated at the physiological pH (COO-)
  • Hydrogen group
  • Variable Group: R = Residue/Rest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a Zwitter ion

A

Compound with one positively and one negatively charged group

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

Types of Noncovalent (Weak) Interactions in Aqueous Solutions

A

Ionic Bonding, Hydrogen Bonding, Hydrophobic Interaction, Van der Walls: ‘microgravity’

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

What is Ionic Bonding?

A

When a negative and a positive charge are attracted to each other. (Na+ and Cl- or COO- and NH3+)

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

What is Hydrogen Bonding?

A

It involves polar bonds, including H-bonding groups like OH-, SH-, NH2, amido)

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

What is a hydrophobic interaction?

A

Involves Nonpolar bonds, primarily hydrocarbon, ether

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

What is Van der Walls, ‘microgravity’ ?

A

When two masses get close enough to each other, then there is an additional gravitational force created between them

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

How many Standard Amino Acids are there in Proteins

A

20

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

Name the different groups of Standard Amino Acids

A

-Nonpolar (aliphatic), polar (uncharged), aromatic, negatively charged, positively charged

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

Name characteristics of the non-polar/aliphatic (amino acid) R groups

A
  • R Group is non-polar (hydrophobic)

- Will interact with other hydrophobic groups through hydrophobic interaction

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

Name the Nonpolar (aliphatic) amino acids

A

Glycine, Alanine, Proline, Valine, Leucine, Isoleucine, Methionine

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

What is the only non-chiral among the 20 standard AAs?

A

Glycine

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

What is the only AA with ring between R and alpha-amino group?

A

Proline

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

What is one of only 2 sulfur-containing AAs? (One in the Nonpolar, aliphatic R group)

A

Methionine

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

Characteristics of Polar, uncharged R groups

A

-Polar groups foster hydrogen bonding

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

Which of the points (A-E) depicted is Kd?

A

C

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

Name group A

A

Alpha Carbon

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

Name Group B

A

Carboxyl Group

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

What is Group C

A

Amino Group

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

Glycine

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

Alanine

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

Proline

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

Valine

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

Leucine

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

Isoleucine

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

Methionine

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

Name the circled part of the Amino Acid

A

Thioether

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

Serine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q
A

Threonine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q
A

Cysteine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q
A

Asparagine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q
A

Glutamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q
A

Phenylalanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q
A

Tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q
A

Tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

The three Amino Acids that are Aromatic and the two features they share:

A

Phenylalanine, Tyrosine, Tryptophan

Alternating double bounds in ring structure (aromatic)
Absorb UV light around 280 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q
A

Lysine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q
A

Arginine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q
A

Histidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q
A

Aspartate (aspartic acid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q
A

Glutamate (glutamic acid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What role does Carnitine play in the body?

A

Transport of fatty acids into mitochondria for breakdown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the purpose of creatine?

A

To store back up energy in skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is condensation?

A

H20 Released while covalent bond formed between two molecules & catalyzed by ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Hydrolysis is…

A

Covalent bond broken that requires H2O and catalyzed by peptidases and prteases.

46
Q

What is a Dipeptide

A

Dimer of two amino acids

47
Q

What is a Peptide Bond?

A

Amide (amido group) formed by condensation of two amino acids.

48
Q

What is the nature of the backbone of a polymer?

A

Repetitive. From Left to Right, repeats a three component pattern.
Ca - CO - NH - - Ca - CO - NH - …

49
Q

What is the C-Terminus?

A

the last amino acid of a polymer.

50
Q

What is the N-terminus of a polymer

A

The first Amino Acid of a peptide chain.

51
Q

The first Protein sequenced in 1953 was?

A

Insulin

  • Took 10 years
  • 2 different polypeptides
  • 2 disulfide bonds between the polypeptides and one disulfide bond within one of the polypeptides
52
Q

What are the symptoms of sickle cell anemia?

A
  • Muscle pain
  • Weakness
  • Dizziness
  • Shortness of Breath
  • Heart Murmur
  • Death often occurs by age 15, triggered by: physical exertion and infections
53
Q

Sickle cell Anemia is a:

A

genetic disorder

54
Q

Carnitine:

A

Carries fatty acids into the mitochondria

55
Q

In a conjugated protein, a prosthetic group is:

A

A part of the protein that is not composed of amino acids
(fake leg)

56
Q

The secondary structure of the fibrous proteins consists of:

A

Beta-sheet only or alpha helix only, but not both.

57
Q

How many water molecules are released when a hexapeptide is synthesized from free amino acids?

A

9

58
Q

Fe(2+) is protected from ____________ by surrounding nitrogen atoms in the pyrrole ring structure of heme and a nitrogen atom of a histidine

A

Oxidation

59
Q

The interaction of ligands with proteins:

A

Is temporary

60
Q

The heme part of protein in myoglobin is the _____________

A

Prosthetic group

61
Q

In sickle cell anemia, __________ is replaced by ________ in subunit beta

A

Hydrophilic (glu)/hydrophobic (val)

62
Q

What is the most likely weak interaction between the R groups of valine and alanine in an aqueous solution?

A

D. Hydrophobic Interaction

63
Q

Which of the following statements is false?
A. Myoglobin has one oxygen-binding site, whereas hemoglobin has four
B. Myoglobin is a monomer and hemoglobin is an oligometer
C. Myoglobin’s oxygen binding curve is sigmoid while the one of hemoglobin is hyperbolic
D. Myoglobin’s is smaller than hemoglobin
E. Myoglobin and hemoglobin have the function of binding oxygen

A

C. Myoglobin’s oxygen binding curve is sigmoid while the one of hemoglobin is hyperbolic

64
Q

The main stabilizing force in alpha-helices is __________.

A

Hydrogen bonding

65
Q

Two amino acids of the standard 20 contain sulfur atoms. They are _______________.

A

Methionine and cysteine

66
Q

Changing the shape of a molecule by rotating functional groups around a single bond, without breaking it, leads to ___________________.

A

A conformation change

67
Q

The formation of a peptide bond is a _____________.

A

Condensation

68
Q

The chirality of an amino acid results from the fact that its alpha-carbon __________________.

A

Is bonded to four different chemical groups

69
Q

___________ is/are (a) covalent stabilizing force in the tertiary/quaternary structure of many proteins

A

Disulfide bonds

70
Q

Oxygen is a(n) _____________ of hemoglobin

A

Ligand

71
Q

The charge of aspartate at pH 12 is __________

A

-1

72
Q

Some of the typical symptoms of sickle cell anemia are signs of _________

A

Lack of oxygen supply to the body

73
Q

Which of the following is NOT a fibrous protein?
A. Alpha-Keratin
B. Collagen
C. Insulin

A

C. Insulin

74
Q

~~~
Which of the following involve a double bond?
A.cis/trans isomers
B. Enantiometers
C. Diastereometers
D. Anometers

A

A. Cis/trans isomers

75
Q

Which modification step of tropocollagen synthesis is dependent on vitamin C?
A. Hydroxylation
B. Glycosylation
C. Disulfide bond formation
D. Removal of C- and N-termini

A

A. Hydroxylation

76
Q

Which of the following are considered ligands and have an allosteric effect on hemoglobin, which leads to a change in affinity for O2?

1) O2
2) BPG
3) CO
4) Heme

A. 1 only
B. 2 only
C. 1,2,3
D. 1,2,3, and 4

A

C. 1,2,3

77
Q

In titration curves pKa values are determined by finding the pH values that correspond with __________ and the label of the y-axis is ________
A. Endpoints; pH
B. Endpoints; equivalents (or mL) OH-
C. Midpoints; pH
D. Midpoints; equivalents (or mL) OH-

A

C. Midpoints, pH

78
Q

Name the two-covalent (enzyme-catalyzed) modification steps that occur in the rER and briefly explain why these modifications lead to better/stronger collagen

A
  1. Hydroxylation
    - Additional -OH for: increased hydrogen bonding and/or increased sites for glucosolation
  2. Glucosulation
    - Increases -OH for increased hydrogen bonding
79
Q

How does the body adjust to high altitudes in the short term?

A

Increased BPG—>Lowers O2 affinity of Hb—>Increases O2 available to tissue

80
Q

How does the body adjust to high altitudes in the long term (few weeks)?

A

Increased RBCs (Increased Hb)—> Increased # of O2-binding sites—>Delivery of needed amount of O2 (Despite lower saturation in lungs)

81
Q

The depicted Formula shows a _______________.

A

disulfide

82
Q

The Pka values of the depicted amino acid are: pK1 = 2.17, pK2 = 9.04, pKr = 12.48. The pI of this amino acid is:

A

10.76

83
Q

What functional groups are present on this molecule?

A

Hydroxyl and Aldehyde

84
Q

The depicted Molecule is an __________________.

A

anhydride

85
Q

The functional group between R1 and R2 in the depicted compound is a(n) _________________.

A

Ester

86
Q

The name of the amino acid #1 in the depicted oligopeptide is _____________________.

A

Tyrosine

87
Q

The depicted amino acid has a(n) _______________ R-Group.
A. positively charged (basic)
B. Non-polar (aliphatic)
C Uncharged Polar
D. Negatively charged (acidic)

A

C. Uncharged Polar

88
Q

The configuration at the α-carbon of the vast majority of naturally occurring amino acids is _________.

  1. L
  2. D
A

L

89
Q

___________ has a pKr that is close to 7 and hence is commonly found at the active site of enzymes.

a. Proline
b. Cysteine
c. Glycine
d. Lysine
e. Histidine

A

e. Histidine

90
Q

Hydrophobic interaction occurs between ___________ R-goups.

a. Nonpolar, aliphatic
b. Polar, uncharged
c. Aromatic
d. Positively charged
e. Negatively charged

A

a. nonpolar, aliphatic

91
Q

The only uncommon amino acid found in proteins that is modified pre-translation is ___________.

a. selenocysteine
b. hydroxyproline
c. hydroxylysine
d. carboxyglutamate

A

a. Selenocysteine

92
Q

Carnitine (an uncommon amino acid…

a. transports fatty acids into the mitochondria
b. is an intermediate of bile biochemistry
c. is an intermediate of the urea cycle
d. stores phosphate in muscle tissue

A

a. transports fatty acids into the mitochondria

93
Q

The C-terminal amino acid in the depicted tripeptide is:

A

alenine

94
Q

At pH 4, aspartate has an overall charge of __________.

A

d. +1

95
Q

The pI of aspartate is _____________.
(pK1 = 1.88, pK2 = 9.60, pKr = 3.65)

a. 1.88
b. 2.77
c. 3.65
d. 5.77
e. 6.63
f. 9.60

A

b. 2.77

96
Q

T or F

Every amide bond is a peptide bond.

A

False

97
Q

T or F

Every peptide bond is an amide bond.

A

True

98
Q

___________ is a prosthetic group of hemoglobin.

a. Histidine
b. CO
c. O2
d. Heme
e. Myoglobin

A

D. Heme

99
Q

A ligand is______________________…

a. Bound non specifically by its protein.
b. a chemical species that is reversibly bound to its protein.
c. always covalently bound to its protein.
d. Always a polypeptide.
e. Always a complex molecular structure

A

B. A chemical species that is reversibly bound to its protein.

100
Q

The heme prosthetic group of hemoglobin consists of a pyrrole-ring system with _________ bound in its center.

A

Fe2+ (Iron)

101
Q

_______________ is a ligand of hemoglobin.

A

O2

102
Q

Fe2+ is protected from ________________ by surrounding nitrogen atoms in the pyrrole ring structure of heme and a nitrogen atom of a histidine.

A

Oxidation

103
Q

Myoglobin shows a ______________ O2-binding curve.

A

Hyperbolic

104
Q

BPG (2, 3-bisphosphoglycerate) plays a role in adaptation of the human body to lower pO2 at higher altitudes by…..

A

binding to an allosteric binding site on the hemoglobin and lowering hemoglobin’s affinity for O2.

105
Q

_____________ Can be a trigger of an episode of sickle cell anemia.

a. Exercise
b. Hard physical labor
c. An infection
d. All of the above

A

D. All of the above

106
Q

The mutation behind scale cell anemia leads to the replacement of ________________ by ___________ in subunit β.

A

hydrophilic GLU

hydrophobic VAL

107
Q

Carriers of the sickle cell trait have protection from

A

Malaria

108
Q

They typical symptoms of sickle cell anemia are signs of _____________.

a. reaction by the immune system to the condition
b. lack of oxygen supply to the body
c. an autoimmune reaction
d. a genetic disorder

A

B. lack of oxygen supply to the body

109
Q

The chiral it’s of an amino acid results in the fact that it’s alpha carbon
A. Is symmetric
B. Has no net charge
C. Bonded to 4 different chemical groups
D. Is in the l-absolute
E. Is the l-absolute configuration

A

C. Bonded to 4 different chemical groups.

110
Q

Which modification step of troop collagen synthesis is dependent on Vitamin C.

A. Hydroxylation
B. Glycosylation
C. Disulfide bond formation
D. Removal of the C and N termini

A

A. Hydroxylation