BMB Exam 1

The affinity of adult hemoglobin and fetal hemoglobin differ with respect to oxygen and 2, 3-BPG. Which of the following correctly describes fetal and adult hemoglobin?

Fetal hemoglobin has a higher affinity for O2 than adult hemoglobin at the same partial pressure of O2.

Which of the following sets of amino acids, read 1, 2, 3 from left to right contains amino acids that are classified as: 1) basic; 2) aromatic; and 3) aliphatic, branched

Lysine; Tryptophan; Leucine

In methemoglobin, the central iron of the heme ring is in the 3+ oxidation state and there is CO2 bound to it

False

One reason that mutations in DNA sequence might not lead to a difference in amino acid sequence, is that some amino acids can be coded by more than one codon, and so a change in codon sequence may not result in a change of amino acid sequence

True

Select the true statement regarding occurrences in capillaries surrounding metabolically active tissues (red blood cells = RBCs):

Cl- will be transported into RBCs.

Some carbohydrates are macromolecules that can act as a fuel source, and others can provide structure to an organism.

True

Covalent bond energy is equal to amount of energy released when a covalent bond is broken.

False

Select the correct statement, considering eukaryotic processes.

The genetic information in DNA is converted into RNA by transcription.

Which of the following is not a weak intermolecular interaction found in biological systems:

Disulfide bond

Which of the following is the major driving force in protein folding?

The entropic effect of water

Change in O2 affinity in hemoglobin is due to cooperativity, and results from allosteric changes in a monomer upon O2 binding that affects the tetramer as a whole.

True

The presence of thymine in DNA rather than cytosine is one reason that DNA is more stable over time than RNA. True False

False

Choose the true statement:

Denaturing a protein disrupts its native conformation.

Choose the true statement:

Amyloid can form when proteins misfold resulting in abnormal beta-sheet formation that encourages fibrillar organization.

Choose the true statement:

Arginine is a conservative substitution for glutamine.

You are walking to class - which of these reactions would predominate in RBCs in the capillaries in your muscles?

H2O + CO2� H2CO3

Please select the true statement:

Hemoglobin in the tense state has a lower affinity for oxygen than hemoglobin in the relaxed state.

Proline does not have chiral stereochemistry at the alpha carbon, because it is an imino acid.

False

Please identify the TRUE statement regarding water:

Water is permanent dipole with partial charges at the oxygen and each of the hydrogen atoms

Select the TRUE answer regarding peptides.

Peptide bonds show partial double bond characteristics

tRNA is an adapter RNA that covalently binds to amino acids and hydrogen bonds with codons in the RNA template

True

If the molar concentration of a product increases relative to molar concentration of the starting reactants, this will have what effect on the free energy of the reaction?

It will cause ?G to increase.

Chimp myoglobin and human myoglobin represent protein paralogs.

False

The distal histidine in hemoglobin is a coordination point for the heme central iron

False

Nucleotides are held together in the nucleic acid polymer by covalent phosphodiester bonds

True

Catabolic pathways are largely divergent, oxidizing and exergonic overall.

True