BMSC 200 - Module 3 Exam Questions
with Verified Answers
Disulfide Bond - ANSWER-A covalent linkage formed between the sulfhydryl groups
of two cysteine residues. This is important for protein stabilization
Amphoteric - ANSWER-Capable of accepting and donating protons, able to serve as
both an acid and a base.
Diprotic - ANSWER-A molecule with two functional groups that can accept/donate
protons; corresponding to two buffering regions on a titration curve.
Triprotic - ANSWER-A molecule with three functional groups that can accept/donate
protons; corresponding to three buffering regions on a titration curve.
Isoelectric Point - ANSWER-The pH at which the molecule has a net charge of zero.
It is calculated by adding the pKa's of the molecules and dividing by 2.
Peptide Bond - ANSWER-A covalently linkage formed between the carboxyl group of
one amino acid to the amino group of a second amino acid through condensation
reactions. The primary linkage of all peptide, polypeptide and protein structures
Residue - ANSWER-A single unit within a polymer; for example an amino acid within
a polypeptide chain
What is the difference between peptides, polypeptides and proteins? - ANSWER-
The difference is the length. Polypeptides are longer than peptides and after 51
amino acids polypeptides become into proteins.
Why does a protein have to be atleast 51 amino acids long? - ANSWER-The
shortest protein known is insulin which is a chain of 51 amino acids. So anything less
than 51 amino acids is called a polypeptide.
What are peptides, polypetides and proteins? - ANSWER-They are all linear
polymers of amino acids.
Are amino acids stereoisomers? - ANSWER-Yes, all amino acids, except for glycine
have a chiral carbon and are therefore stereoisomers.
How are the 20 amino acids different? - ANSWER-The 20 amino acids have different
R group side chains linked to a common skeleton. The properties of these side
chains define unique characteristics of amino acids.
, Why is glycine not stereoisomeric? - ANSWER-All amino acids but glycine the alpha
carbon is bonded to four different groups creating a chiral center creating
stereoisomers. Glycine does not have a chiral carbon
What kind of amino acid are biological proteins made from? - ANSWER-Biological
proteins are made almost exclusively from L amino acids.
Abbreviations:
Glycine - ANSWER-Gly
G
Abbreviations:
Alanine - ANSWER-Ala
A
Abbreviations:
Proline - ANSWER-Pro
P
Abbreviations:
Valine - ANSWER-Val
V
Abbreviations:
Leucine - ANSWER-Leu
L
Abbreviations:
Isoleucine - ANSWER-Ile
I
Abbreviations:
Methionine - ANSWER-Met
M
Abbreviations:
Phenylalanine - ANSWER-Phe
F
Abbreviations:
Tyrosine - ANSWER-Tyr
with Verified Answers
Disulfide Bond - ANSWER-A covalent linkage formed between the sulfhydryl groups
of two cysteine residues. This is important for protein stabilization
Amphoteric - ANSWER-Capable of accepting and donating protons, able to serve as
both an acid and a base.
Diprotic - ANSWER-A molecule with two functional groups that can accept/donate
protons; corresponding to two buffering regions on a titration curve.
Triprotic - ANSWER-A molecule with three functional groups that can accept/donate
protons; corresponding to three buffering regions on a titration curve.
Isoelectric Point - ANSWER-The pH at which the molecule has a net charge of zero.
It is calculated by adding the pKa's of the molecules and dividing by 2.
Peptide Bond - ANSWER-A covalently linkage formed between the carboxyl group of
one amino acid to the amino group of a second amino acid through condensation
reactions. The primary linkage of all peptide, polypeptide and protein structures
Residue - ANSWER-A single unit within a polymer; for example an amino acid within
a polypeptide chain
What is the difference between peptides, polypeptides and proteins? - ANSWER-
The difference is the length. Polypeptides are longer than peptides and after 51
amino acids polypeptides become into proteins.
Why does a protein have to be atleast 51 amino acids long? - ANSWER-The
shortest protein known is insulin which is a chain of 51 amino acids. So anything less
than 51 amino acids is called a polypeptide.
What are peptides, polypetides and proteins? - ANSWER-They are all linear
polymers of amino acids.
Are amino acids stereoisomers? - ANSWER-Yes, all amino acids, except for glycine
have a chiral carbon and are therefore stereoisomers.
How are the 20 amino acids different? - ANSWER-The 20 amino acids have different
R group side chains linked to a common skeleton. The properties of these side
chains define unique characteristics of amino acids.
, Why is glycine not stereoisomeric? - ANSWER-All amino acids but glycine the alpha
carbon is bonded to four different groups creating a chiral center creating
stereoisomers. Glycine does not have a chiral carbon
What kind of amino acid are biological proteins made from? - ANSWER-Biological
proteins are made almost exclusively from L amino acids.
Abbreviations:
Glycine - ANSWER-Gly
G
Abbreviations:
Alanine - ANSWER-Ala
A
Abbreviations:
Proline - ANSWER-Pro
P
Abbreviations:
Valine - ANSWER-Val
V
Abbreviations:
Leucine - ANSWER-Leu
L
Abbreviations:
Isoleucine - ANSWER-Ile
I
Abbreviations:
Methionine - ANSWER-Met
M
Abbreviations:
Phenylalanine - ANSWER-Phe
F
Abbreviations:
Tyrosine - ANSWER-Tyr
