QUIZ 3, BICH 410 (MWF 1:50 PM), Friday, Nov. 3, 1995
Clearly circle the letter corresponding to your answer for each problem. There are seven problems, six of which count 3 points, and one is worth 2 points. No partial credit given for multiple-choice questions.
1) Which of the following is not likely to aid in the denaturation of double-stranded DNA?
- A. heating the sample
- B. adding formamide
- C. adding urea
- D. increasing the ionic strength
- E. adjusting to a very basic pH
2) (2 pts) Which is the most highly branched carbohydrate?
- A. amylopectin
- B. cellulose
- C. amylose
- D. sucrose
- E. glycogen
3) The Watson-Crick base pairing scheme for an A-T base pair includes:
- A. a hydrogen bond between two ring nitrogen atoms.
- B. an ionic bond between the positively charged adenine amino group and a negatively polarized keto group.
- C. a hydrogen bond between a keto oxygen and an extracyclic amino group.
- D. both A and B.
- E. both A and C.
4) Which of the following is a heteropolysaccharide?
- A. chitin
- B. starch
- C. glycogen
- D. cellulose
- E. hyaluronate
5) In glycoproteins, the carbohydrate moiety is always attached through the amino acid residues:
- A. aspartate or glutamate.
- B. tryptophan, aspartate, or cysteine.
- C. glutamine or arginine.
- D. asparagine, serine, or threonine.
- E. glycine, alanine, or aspartate.
6) When two carbohydrates are epimers:
- A. one is in the chair conformation and the other in the boat conformation.
- B. they differ in length by one carbon.
- C. one is an aldose, the other a ketose.
- D. one is a pyranose, the other a furanose.
- E. they differ in the configuration around one carbon atom.
7) A single-stranded DNA oligonucleotide 20 nucleotides in length has an approximate molecular weight of:
- A. 2000
- B. 6600
- C. 13,200
- D. 20,000
- E. 33,000