Quiz #10

How many nucleotide bases correspond to a single amino acid?

3

RNA polymerase moves in which direction along the DNA?

3' to 5' along the template strand

Given the locally unwound double strand in Figure 17.3, in which direction does the RNA polymerase move?

3' → 5' along the template strand

Examine the table of codons in Figure 17.2. A possible sequence of nucleotides in the template strand of DNA that would code for the polypeptide sequence phe-leu-ile-val would be

3'-AAA-GAA-TAA-CAA-5'

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

3'-UCA-5'

A peptide has the sequence NH2-phe-pro-lys-gly-phe-pro-COOH. Which of the following sequences in the coding strand of the DNA could code for this peptide?

5'-TTT-CCC-AAA-GGG-TTT-CCC

The genetic code is essentially the same for all organisms. Based on this information, one can logically assume which of the following statements to be correct?

A gene from an organism can theoretically be expressed by any other organism.

The nitrogenous base adenine is found in all members of which of the following groups of molecules?

ATP, RNA, and DNA

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

Any mutation in the sequence is selected against.

Which component is not directly involved in translation?

DNA

In what way might a point mutation in DNA make a difference in the function of a protein?

It might substitute a different amino acid in the active site.

Which enzyme catalyzes RNA synthesis?

RNA polymerase

In comparing DNA replication with RNA transcription in the same cell, which of the following is true only of replication?

The entire template molecule is represented in the product.

____is the synthesis of RNA using the sequence of a DNA template.

Transcription

____is the synthesis of a polypeptide, which occurs using the sequence of the mRNA.

Translation

In the 1920s, Hermann Muller discovered that X-rays caused genetic changes in Drosophila. In a related series of experiments in the 1940s, other scientists discovered that other types of chemicals have a similar effect. A new chemical food additive is developed by a cereal manufacturer. Why is it necessary to test for its ability to cause mutation?

We want to be sure that it increases the rate of mutation sufficiently.

The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single codon. What is the most likely result of this mutation in the protein product?

a polypeptide missing an amino acid

Which of the following mutations is most likely to cause a phenotypic change?

a single nucleotide deletion in an exon coding for an active site of a protein

How can 1 gene with multiple exons result in multiple different polypeptides?

alternative splicing

Each tRNA molecule also has a(n) ___ that base-pairs with the complementary codon of mRNA

anti-codon

In prokaryotes mRNA is translated ____, in eukaryotes mRNA is translated ____.

immediately, after processing in the nucleus.

Regions of DNA sequence that don't code for proteins (non-coding regions) are called ___

introns

What amino acid sequence will be produced based on the following mRNA codon sequence?

met-ser-ser-leu-ser-leu

____ is a number of ribosomes simultaneously translating a single mRNA molecule.

polyribosome

___ signal the initiation of RNA synthesis

promoters

The genetic code is ____ meaning multiple codons can correspond to the same amino acid.

redundant

____ are the site of translation in ALL cell types.

ribosomes

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

several transcription factors

In eukaryotic cells, transcription cannot begin until

several transcription factors have bound to the promoter

Each molecule of ___ carries as specific amino acid to the ribosome to construct polypeptides

tRNA

Known as ____ DNA--> RNA--> protein is a cellular chain of command which governs cells.

the Central Dogma

In the transcription event of the DNA in Figure 17.3, where would the promoter be located?

to the right of the template strand