Biology 2015

Transformation occurs when
a. DNA is transformed into RNA.
b. DNA is transformed into protein.
c. bacteria cannot grow on penicillin.
d. organisms receive foreign DNA and thereby acquire a new characteristic.

The double helix model of DNA resembles a twisted ladder in which the rungs of the ladder are
a. a purine paired with a pyrimidine.
b. A paired with G and C paired with T.
c. sugar-phosphate paired with sugar-phosphate.
d. a 5? end paired with a 3? end.
e. Both a and b are correct

If 30% of an organism’s DNA is thymine, then
a. 70% is purine.
b. 20% is guanine.
c. 30% is adenine.
d. 70% is pyrimidine.
e. Both b and c are correct.

If the sequence of bases in one strand of DNA is 5? TAGCCT 3?,
then the sequence of bases in the other strand is
a. 3? TCCGAT 5?. c. 3? TAGCCT 5?.
b. 3? ATCGGA 5?. d. 3? AACGGUA 5?.

DNA replication is said to be semiconservative because
a. one of the new molecules conserves both of the original DNA strands.
b. the new DNA molecule contains two new DNA strands.
c. both of the new molecules contain one new strand and one old strand.
d. DNA polymerase conserves both of the old strands.

The enzyme responsible for separating double-stranded DNA into single-stranded DNA is
a. DNA helicase.
b. DNA primase.
c. DNA polymerase.
d. DNA ligase.

The central dogma of molecular biology
a. states that DNA is a template for all RNA production.
b. states that DNA is a template only for DNA replication.
c. states that translation precedes transcription.
d. states that RNA is a template for DNA replication.
e. All of these are correct.

If the sequence of DNA on the template strand of a gene is AAA, the mRNA codon produced by transcription will be _______ and will specify the amino acid _______ .
a. AAA, lysine
b. AAA, phenylalanine
c. TTT, arginine
d. UUU, phenylalanine
e. TTT, lysine

If the sequence of bases in the coding strand of a DNA molecule is TAGC, then the sequence of bases in the mRNA will be
a. AUCG.
b. TAGC.
c. UAGC.
d. ATCG.

The portion of the mRNA transcript that gets removed during RNA processing is the
a. exons.
b. introns.
c. poly-A tails.
d. 5? caps.
e. spliceosomes.

During protein synthesis, an anticodon on transfer RNA (tRNA) pairs with
a. DNA nucleotide bases.
b. ribosomal RNA (rRNA) nucleotide bases.
c. messenger RNA (mRNA) nucleotide bases.
d. other tRNA nucleotide bases.
e. All of these are correct.

This is a segment of a DNA molecule. What are (a) the RNA codons, (b) the matching tRNA anticodons, and (c) the sequence of amino acids in the eventual protein?