Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
78 Cards in this Set
- Front
- Back
|
What determines the chemical properties of amino acids? |
the side chain |
|
|
the 20 amino acids encoded by the human genetic code |
proteinogenic amino acids |
|
|
the alpha carbon is a chiral center in every amino acid, making them optically active, except which one? |
glycine |
|
|
all chiral amino acids used in eukaryotes are ____-amino acids |
L |
|
|
What is the only L-amino acid that does not translate to an (S) absolute configuration |
cysteine |
|
|
List all of the amino acids with non-polar, non-aromatic side chains. |
glycine, alanine, valine, leucine, isoleucine, methionine, proline |
|
|
List all of the amino acids with aromatic side chains. |
phenylalanine, tryptophan, tyrosine
|
|
|
List all of the amino acids with polar side chains that are not aromatic. |
serine, threonine, asparagine, glutamine, cysteine
|
|
|
List the amino acids that have acidic (negatively charged) side chains |
aspartate and glutamate |
|
|
List the amino acids that have basic (positively charged side chains |
histidine, lysine, arginine
|
|
|
What amino acids are strongly hydrophobic and more likely to be found in the interior of proteins? |
alanine, valine, leucine, isoleucine, phenylalanine
|
|
|
What amino acids are strongly hydrophilic and most likely to be found on the surface of a protein?
|
aspartate, glutamate, histidine, lysine, arginine, asparagine, glutamine |
|
|
What are the 1 and 3 letter abbreviations for alanine?
|
A, Ala |
|
|
What are the 1 and 3 letter abbreviations for arginine?
|
R, Arg |
|
|
What are the 1 and 3 letter abbreviations for asparagine?
|
N, Asn
|
|
|
What are the 1 and 3 letter abbreviations for aspartate?
|
D, Asp |
|
|
What are the 1 and 3 letter abbreviations for cysteine? |
C, Cys |
|
|
What are the 1 and 3 letter abbreviations for glutamate?
|
E, Glu |
|
|
What are the 1 and 3 letter abbreviations for glutamine?
|
Q, Gln |
|
|
What are the 1 and 3 letter abbreviations for glycine?
|
G, Gly |
|
|
What are the 1 and 3 letter abbreviations for histidine? |
H, His |
|
|
What are the 1 and 3 letter abbreviations for isoleucine?
|
I, Ile |
|
|
What are the 1 and 3 letter abbreviations for leucine?
|
L, Leu |
|
|
What are the 1 and 3 letter abbreviations for lysine? |
K, Lys |
|
|
What are the 1 and 3 letter abbreviations for methionine?
|
M, Met |
|
|
What are the 1 and 3 letter abbreviations for phenylalanine?
|
F, Phe |
|
|
What are the 1 and 3 letter abbreviations for proline?
|
P, Pro |
|
|
What are the 1 and 3 letter abbreviations for serine?
|
S, Ser |
|
|
What are the 1 and 3 letter abbreviations for threonine?
|
T, Thr |
|
|
What are the 1 and 3 letter abbreviations for tryptophan?
|
W, Trp |
|
|
What are the 1 and 3 letter abbreviations for tyrosine?
|
Y, Tyr |
|
|
What are the 1 and 3 letter abbreviations for valine?
|
V, Val |
|
|
What is the acidic group of every amino acid?
|
carboxylic acid |
|
|
What is the basic group of every amino acid |
amino group |
|
|
a species that can accept or donate a proton?
|
amphoteric species |
|
|
ionizable groups tend to _____________ protons under acidic conditions and ______________ them under basic conditions |
gain, lose |
|
|
the pH at which, on average, half the molecules of that species are deprotonated or when [HA]=[A-] |
pKa
|
|
|
if the pH |
protonated
|
|
|
if the pH>pKa then a majority of species will be ______________. |
deprotonated |
|
|
the pKa1 of amino acids is for the carboxyl group and is usually around _______ |
2 |
|
|
the pKa2 of amino acids is for the amino group and is usually around _______ |
9-10 |
|
|
how many pKas will there be for amino acids with an ionizable side chain?
|
3 |
|
|
When do amino acids tend to be positively charged? |
very acidic pH |
|
|
When do amino acids tend to be zwitterions? |
pH=7.4
|
|
|
When do amino acids tend to be negatively charged? |
very alkaline pH
|
|
|
When does a solution act as a buffer? |
pH of solution=pKa of buffer
|
|
|
the pH at which the molecule is electrically neutral? |
isoelectric point (pI) |
|
|
The pI of amino acids with non-ionizable side chains is around _____ |
6 |
|
|
The pI of amino acids with acidic side chains is ____________ 6 and the pI of amino acids with basic side chains is ____________ 6. |
below, above |
|
|
these are composed of amino acid subunits, or residues
|
peptides |
|
|
the term used for relatively small peptides, up to about 20 residues |
oligopeptide |
|
|
the term used for longer peptides, greater than 20 residues |
polypeptides |
|
|
a specialized form of an amide bond that forms between the COO- group of one amino acid and the NH3+ group of another amino acid |
peptide bond |
|
|
What kind of reaction is peptide bond formation an example of? |
condensation or dehydration |
|
|
peptides are drawn, read, and synthesized by ribosomes in what order? |
N-terminus to C-terminus |
|
|
In order for humans to digest proteins they need to break them down into their component amino acids through what type of reaction? |
hydrolysis |
|
|
What 2 hydrolytic enzymes catalyze hydrolysis in living organisms? |
trypsin and chemotrypsin |
|
|
This hydrolytic enzyme cleaves at the carboxyl end of arginine and lysine. |
trypsin |
|
|
This hydrolytic enzyme cleaves at the carboxyl end of phenylalanine, tyrosine and tryptophan |
chemotrypsin |
|
|
polypeptides that range from just a few amino acids in length up to thousands |
proteins |
|
|
a recipe for making thousands of proteins |
genetic code |
|
|
What are the 4 levels of structure in proteins? |
primary, seconday, tertiary, quaternary |
|
|
the linear arrangement of amino acids coded in an organism's DNA
|
primary structure |
|
|
What laboratory technique can be used to determine the primary structure of a protein? |
sequencing |
|
|
What are the 2 main secondary structures that result from hydrogen bonding? |
alpha helix and beta pleated sheet |
|
|
a rod-like structure in which the peptide chain coils clockwise around a central axis and these are an important component in the structure of keratin
|
alpha helix |
|
|
a fibrous structural protein found in human skin, hair and fingernails
|
keratin |
|
|
the primary protein component of silk fibers that is composed of beta sheets |
fibroin |
|
|
What amino acid is rarely found in alpha helices because it induces a kink in the peptide chain when it is found in the middle of the alpha helix? |
proline |
|
|
the type of protein that resemble long sheets or strands; collagen is an example |
fibrous protein |
|
|
the type of protein that tends to be spherical |
globular protein |
|
|
a protein's three dimensional shape |
tertiary structure |
|
|
the bonds that form when 2 cysteine molecules become oxidized to form cystine; these bonds create loops in the protein chain and determine how wave or curly human hair is
|
disulfide bonds |
|
|
when a protein loses its structure and thus loses its function |
denaturation |
|
|
this is the only structure that all proteins do not have |
quaternary structure |
|
|
these proteins derive part of their function from covalently attached molecules called prosthetic groups |
conjugated proteins |
|
|
proteins with lipid, carbohydrate, and nucleic acid prosthetic groups are referred to as __________, ___________, and _____________. |
lipoproteins, glycoproteins, nucleoproteins |
|
|
What are the 2 main causes of denaturation? |
heat and solutes |
