Exam #1 Flashcards
A repeating structural unit in a multimeric protein is known as a(n):
motif
The chirality of an amino acid results from the fact that its alpha-carbon:
Is bonded to four different chemical groups
Sterioisomers that are non-superimposable mirror images of each other are known as:
enantiomers
Roughly how many amino acids are there in one turn of an alpha-helix?
3.6
The formation of a peptide bond between two amino acids is an example of a(n) _____________ reaction.
condensation
A reaction with a _____________ delta H and ________ delta S, will never be spontaneous.
positive, negative
Which of the following is the best explanation for the hydrophobic effect?
It is caused by the affinity of water for hydrophobic groups.
Which of the following statements concerning structure of the B-form DNA double helix is true?
A rotation of 36 degrees per nucleotide occurs, so that every 10 nucleotides a full turn of the helix has been accomplished.
In Sanger (or chain terminator) dideoxy DNA sequencing, DNA polymerase is used to add nucleotides to the __ end of the growing polynucleotide chain.
3’
In a protein, the most conformationally restricted amino acid is ________ ; the least conformationally restricted is __________.
Proline ; Glycine
Discovered that the X-ray diffraction reveals phosphate-sugar backbone is outside
Franklin
Discovered that A+T = C+G
Erwin Chargaff
Proposed 3D double helix model based upon X-Ray diffraction data
Watson and Crick
What type of residues are typically found in the interior of a water-soluble globular protein. Briefly describe why.
Nonpolar residues are found on the inside of the double helix because they are hydrophobic. This stabilizes the proteins.
