EA Peptides and Amino Acids

Question 1

In the peptide, MERRYCHRISTMAS, _____ serves as the C-terminus while ______ serves as the N-terminus. (Give the full name of the amino acids).

Answer 1

Serine
Methionine

Question 2

Among the given statements, which ones correctly describe the commonality in dopamine and epinephrine?

• associated with sensation of pleasure
• synthesized in the adrenal gland
• monoamine compounds
• synthesized from tyrosine only
• formation involves esterification
• anionic in nature
• involve a transmethylation reaction
• hormones
• phenolic

Answer 2

They are phenolic compounds

They are monoamine compounds

Question 3

name all essential amino acid (PVT TIM HALL)

Answer 3

Phenylalanine
Valine
Threonine
Tyrosine
Isoleucine
Methionine
Histidine
Arginine
Leucine
Lysine

Question 4

true for peptide bond formation?

dehydration of reacting functional group
results to deamination of amino acid
how nucleic acids are synthesized
cannot be formed between identical amino acids
results to the formation of an amino group
results in the formation of an amide functional group
decarboxylation of amino acid
occurs in sER
occurs in nucleus

Answer 4

dehydration of reacting amino functional groups

formation of amide group

Question 5

In the peptide, HAPPYNEWYEAR, there are a total of ___ peptide bonds and ___molecules of water were removed in its formation.

Answer 5

11, 11

Question 6

How will you describe the properties of the peptide bond?

peptide bond can be protonated
peptide bond can be deprotonated
cis- in configuration as it is more stable in nature
peptide bond can rotate around its bonding axis
peptide bond undergoes resonance
peptide bond is three dimensional
cyclic in nature
acidic in nature
trans-configuration as it is more stable in nature

Answer 6

The peptide bond undergoes resonance.

It is trans- in configuration as it more stable in nature.

Question 7

How are epinephrine and noradrenaline related? I. They are synthesized in the adrenal cortex. II. They have a common amino acid precursor. III. They are both hormones and neurotransmitters IV. They are cationic in nature. V. They bind to the same cell surface receptors.

Answer 7

II, III, IV, and V. (2, 3, 4, and 5)

Question 8

which two amino acids have least solubility in water

Answer 8

tryptophan
phyenylalanine

Question 9

How are oxytocin and vasopressin related? I. They are synthesized in the hypothalamus. II. They have 8 peptide bonds. III. They are cyclic peptides. IV. They have disulfide bond. V. They influence social bonding behaviors.

Answer 9

all

Question 10

Which of the following amino acids are aromatic in nature?

Answer 10

Phenylalanine
Tryptophan

Question 11

Which of the following is true for all amino acids?

positively charged
primary amine
acidic in nature
chiral in nature
amino and carboxy moieties
amphipathic in nature
neutral in net charge
amphoteric in nature
left-handed molecules

Answer 11

amino and carboxyl
amphoteric in nature