BIO Ch. 17 Review

RNA

During splicing, which molecular component of the spliceosome catalyzes the excision reaction?

2

If proteins were composed of only 12 different kinds of amino acids, what would be the smallest possible codon size in a genetic system with four different nucleotides?

RNA polymerase II

In eukaryotes there are several different types of RNA polymerase. Which type is involved in transcription of mRNA for a globin protein?

RNA polymerase uses RNA as a template, and DNA polymerase uses a DNA template.

In which of the following actions does RNA polymerase differ from DNA polymerase?

their presence allows exons to be shuffled.

Introns are significant to biological evolution because

RNA acts as an expendable copy of the genetic material.

Using RNA as a template for protein synthesis instead of translating proteins directly from the DNA is advantageous for the cell because

exon

A mutation in which of the following parts of a gene is likely to be most damaging to a cell?

Any mutation in the sequence is selected against.

A part of the promoter, called the TATA box, is said to be highly conserved in evolution. Which might this illustrate?

3' UCA 5'.

A particular triplet of bases in the template strand of DNA is 5' AGT 3'. The corresponding codon for the mRNA transcribed is

an accumulation of A and no production of B and C

Enzyme A Enzyme B A------------->B------------->C Figure 17.1 A mutation results in a defective enzyme A. Which of the following would be a consequence of that mutation?

2

Enzyme A Enzyme B A------------->B------------->C Figure 17.1 According to Beadle and Tatum's hypothesis, how many genes are necessary for this pathway?

excision of introns.

Once transcribed, eukaryotic mRNA typically undergoes substantial alteration that includes

If UGA, usually a stop codon, is found to code for an amino acid such as tryptophan (usually coded for by UGG only).

The "universal" genetic code is now known to have exceptions. Evidence for this could be found if which of the following is true?

8

The enzyme polynucleotide phosphorylase randomly assembles nucleotides into a polynucleotide polymer. You add polynucleotide phosphorylase to a solution of adenosine triphosphate and guanosine triphosphate. How many artificial mRNA 3 nucleotide codons would be possible?

DNA was the first genetic material.

The genetic code is essentially the same for all organisms. From this, one can logically assume all of the following except

ATP, RNA, and DNA

The nitrogenous base adenine is found in all members of which group?

several transcription factors (TFs)

Transcription in eukaryotes requires which of the following in addition to RNA polymerase?

exons

What are the coding segments of a stretch of eukaryotic DNA called?

an RNA with enzymatic activity

What is a ribozyme?

rRNA

What is the most abundant type of RNA?

They join together to form a large structure called the spliceosome.

Which of the following is (are) true of snRNPs?

RNA polymerase binds to the promoter region to begin transcription.

Which of the following is true for both prokaryotic and eukaryotic gene expression?

a triplet in the same reading frame as an upstream AUG

Which of the following nucleotide triplets best represents a codon?

proline-threonine.

tRNA Anticodon Amino Acid GGC Proline CGU Alanine UGC Threonine CCG Glycine ACG Cysteine CGG Alanine Figure 17.3 A part of an mRNA molecule with the following sequence is being read by a ribosome: 5' CCG-ACG 3' (mRNA). The following charged transfer RNA molecules (with their anticodons shown in the 3' to 5' direction) are available. Two of them can correctly match the mRNA so that a dipeptide can form. The dipeptide that will form will be: