Chem 336 - Spring 1999 - Organic Chemistry III
Portland State University - Dr. Carl C. Wamser

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Chapter 28 Pre-Quiz

(1 point each)

1. The difference between a nucleotide and a nucleoside is that a nucleoside

a) has a phosphate ester linkage

b) doesn't have a phosphate ester linkage

c) is attached to ribose

d) isn't attached to ribose

2. If codons consisted of only a pair of bases (instead of three) how many different codes would there be (using the usual four possible bases in the codes)?

a) 4

b) 8

c) 16

d) 32

e) 64

3. The mRNA codon ACG directs for which amino acid?

a) Ala

b) Arg

c) Met

d) Thr

e) Val

4. Read from the 5' end, a DNA sequence TGCTA would serve as a template for synthesis of an RNA that reads (also from the 5' end)

a) ACGAT

b) TAGCA

c) ATCGT

d) none of the above

5. A piece of DNA that consisted of 6000 bases (6kb) would have a molecular weight of about

a) 60,000

b) 600,000

c) 1,200,000

d) 2,000,000