UNE Biochem Midterm Questions
With Complete Solutions
primary structure of protein correct answer: linear sequence of
amino acids in the polypeptide chain
secondary structure of protein correct answer: alpha helix and
beta pleated sheet
alpha helix correct answer: formed when the carbonyl group of
peptide bond forms a hydrogen bond with the amide nitrogen of
another peptide 4 aa down the chain; proline is not commonly
found among these structures
beta sheets correct answer: can be parallel or antiparallel
peptide chains forming rows or strands held together by
intramolecular H bonds between carbonyl oxygen atoms and
amide H atoms in an adjacent chain
bends, turns, or loops correct answer: short stretches of the
polypeptide chain form these structures that are stabilized by
hydrogen bonds
tertiary structure correct answer: aka super secondary
structures; total 3D conformation of an entire polypeptide chain
including interactions between alpha-helices, beta-sheets, and
any other loops, turns or bends
, domain correct answer: section of a protein sufficient to
perform a particular chemical or physical task
quaternary structure correct answer: combination of two or
more tertiary subunits that work together as one functioning unit
hemoglobin correct answer: travels in the blood inside an RBC
to deliver oxygen to tissues; sigmoidal binding curve
myoglobin correct answer: remains in the heart and skeletal
muscle to bind oxygen released by hemoglobin; hyperbolic
curve
apoprotein correct answer: a protein missing its ligand or
ligands
holoprotein correct answer: a protein with its ligand so it is able
to function
cooperativity correct answer: when oxygen binds to the iron at
one of the Hb binding sites, it pulls on the histidine, which pulls
on the alpha-helix, changing the conformation of the globin;
when oxygen binds to one heme it is more likely to bind a
second molecule of oxygen
tense state of hemoglobin correct answer: low affinity for
oxygen
relaxed stated of hemoglobin correct answer: high affinity for
oxygen
With Complete Solutions
primary structure of protein correct answer: linear sequence of
amino acids in the polypeptide chain
secondary structure of protein correct answer: alpha helix and
beta pleated sheet
alpha helix correct answer: formed when the carbonyl group of
peptide bond forms a hydrogen bond with the amide nitrogen of
another peptide 4 aa down the chain; proline is not commonly
found among these structures
beta sheets correct answer: can be parallel or antiparallel
peptide chains forming rows or strands held together by
intramolecular H bonds between carbonyl oxygen atoms and
amide H atoms in an adjacent chain
bends, turns, or loops correct answer: short stretches of the
polypeptide chain form these structures that are stabilized by
hydrogen bonds
tertiary structure correct answer: aka super secondary
structures; total 3D conformation of an entire polypeptide chain
including interactions between alpha-helices, beta-sheets, and
any other loops, turns or bends
, domain correct answer: section of a protein sufficient to
perform a particular chemical or physical task
quaternary structure correct answer: combination of two or
more tertiary subunits that work together as one functioning unit
hemoglobin correct answer: travels in the blood inside an RBC
to deliver oxygen to tissues; sigmoidal binding curve
myoglobin correct answer: remains in the heart and skeletal
muscle to bind oxygen released by hemoglobin; hyperbolic
curve
apoprotein correct answer: a protein missing its ligand or
ligands
holoprotein correct answer: a protein with its ligand so it is able
to function
cooperativity correct answer: when oxygen binds to the iron at
one of the Hb binding sites, it pulls on the histidine, which pulls
on the alpha-helix, changing the conformation of the globin;
when oxygen binds to one heme it is more likely to bind a
second molecule of oxygen
tense state of hemoglobin correct answer: low affinity for
oxygen
relaxed stated of hemoglobin correct answer: high affinity for
oxygen
