Study sets, textbooks, questions
Upgrade to remove ads
biochemistry exam 1 (me)
Terms in this set (71)
what metal ions is present in myoglobin?
what is the total charge of arginine at pH 0? The pKa values of arginine are 9.04, 2.17, and 12.48.
what is the average mass of an amino acid in amu (or g/mol)?
the alpha helix
is an example of protein SECONDARY structure and is stabilized by hydrogen bonding between the i and i+4 residues
has a glycine at every third residue,
contains hydroxylated proline residues,
and requires vitamin C for its maturation
true/false: hemoglobin is a very good example of protein quarternary structure
in a solution of potassium acetate at a pH of 8.76, what is the molar ratio of conj base to acid ([A-]/[HA])? The pKa for acetic acid is 4.76
(8.76=4.76+logx) => pH=pKa+log([A-]/[HA])
important components of cell membranes
important WEAK intermolecular forces in biochemistry include....
van der waals interactions AND hydrogen bonding
for an acid-conjugate base pair, when the pH is equal to the pKa, the following is true:
the ACID concentration is the SAME of that of the conjugate base
tyrptophan is an example of...
a hydrophobic amino acid
a lack of carbonic anhydrase in red blood cells would...
cause hemoglobin to RETAIN some of its oxygen
beta sheets have...
an almost fully extended peptide strand
2,3 BPG _____ the oxygen binding affinity of hemoglobin
what is the equation for isoelectric point of amino acids with hydroPHILIC basic side chains (positively charged)?
ex) lysine, arginine, histidine
what is the equation for isoelectric point of amino acids with hydroPHOBIC neutral side chains?
ex) glycine, alanine, valine, leucine, isoleucine, methionine, proline, phenylalanine, tryptophan
what is the equation for isoelectric point of amino acids with acidic side chains (negatively charged)?
ex) aspartate, glutamate
draw histidine in equilibirum at a pH of 6.0
(see pg 42 of the text)
which amino acids have hydrophobic side chains? (neutral charge)
glycine, alanine, valine, leucine, isoleucine, methionine, proline, phenylalanine, and tryptophan
[gavl, im pretty phony, tristan]
which amino acids are polar?
serine, threonine, tyrosine, cysteine, asparagine, glutamine
[sara, theyre trying cattle as gluten]
which amino acids are hydrophilic, positively charged, and basic?
lysine, arginine, histidine
[liars are history]
which amino acids are negatively charged with ACIDIC side chains?
aspartate and glutamate
sketch a titration curve for H3PO4 and label pka values. pk values=2.0, 7.0, and 12.0. draw the chemical structures of the species at each pka/ph value. label the axes and number them properly
(see exam and notes in red notebook)
draw the structure of a heme
erythrocytes are chock full of ______
hg is a red blood cell protein that carries oxygen from ___ to ___
carries oxygen from the lungs to the tissues.
hg is an allosteric protein that displays cooperativity in oxygen binding and release
mg binds oxygen in ____ cells [NOT COOPERATIVE]
oxygen binding in mg is measured as a function of the ________
partial pressure of oxygen (pO2)
___ has more than one O2 binding site, and they communicate with each other. [cooperativity]
at low oxygen pressure, ___ has a HIGH efficiency for oxygen
___ releases O2 to ___
hg releases O2 to mg
what allosteric regulators cause additional O2 to be released from hg? 
metabolites (2,3 BPG), pH, and CO2
___ is a SINGLE polypeptide chain consisting mainly of alpha helices arranged to form a globular structure
mg and hg bind oxygen at a ____, a bound prosthetic group also called a cofactor
hb is a ____ protein with 4 subunits
show the formation of a peptide bond from two individual amino acids
(see quiz 1)
calculate the concentration of acetic acid and acetate ion in a 0.5M acetate buffer at a pH of 5. the pka of acetic acid is 4.76. show all calculations
(see quiz 1)
how many amino acids are there in one turn of an alpha helix?
name the intermolecular force that helps stabilize the alpha helix
a lipid bilayer consists of ___ heads and ___ tails
nonpolar hydrophobic tails and polar hydrophilic head
true/false: van der waals interactions are weaker than hydrogen bonding interactions on a per mole basis
the mitochondria is the site of many ____ biosynthetic reactions
true/false: 2,3 BPG lowers affinity of O2 for hg
process in which which hemoglobin's binding affinity for oxygen is also reduced by a lower pH and high concentration of carbon dioxide.
what is the most oxidized form of carbon?
what is the most reduced form of carbon?
saturated hydrocarbon of a fatty acid
what is protein folding powered by?
what is pH a measure of?
the H+ concentration of a solution
the lower the pH, the ____ the H+ concentration
larger kA = _____
smaller pka = _____
what is the inflection point?
where the amount of conjugate base= amount of conjugate acid and pH=pKa
henderson hasselbach equation
what is the equivalence point?
moles of base=moles of acid
a buffer is most effective at a pH value ____pH value near the pKa
acid= proton ____
base= proton ____
pka is the pH at which the acid is ____?
what are the 2 main ways of depicting chirality in amino acids?
1) fischer projections (CONSTITUENT ATOMS)
2) stereochemical renderings (SHAPE)
what are the 4 components of an amino acid?
carboxylic acid (COO-), amino group (H3N+), hydrogen atom (H), and a distinctive side chain (R group)
all amino acids except for ____ are chiral (2 mirror images)
L isomers are constituents of _____
D isomers are constituents of ____
amino acids are linked by ____ bonds
peptide bonds / (amide bonds)
what is the other name for peptide bonds?
each amino acid in a protein is called a _______
peptide bond begins with ___ and ends with ____
begins with amino terminal end and ends with carboxyl terminal end
_____ bonds: have partial double bond character and
are responsible largely for observing elements of SECONDARY structure
what metals are essential for life? (4)
Fe, Cu, Zn, and Co
___ and ___ lower the affinity of hg
H+ and CO2
rise per residue is ___
_____ residues per turn
rise per residue is 1.5 A
3.6 residues per turn
Other sets by this creator
biochemistry exam 4
biochemistry exam 3
biochemistry exam 2
COMM 1000 Final terms
Other Quizlet sets
Geography Final Exam
Persons and Personal Identity
Azure Test 5