Organisation of Eukaryotic Genome; Regulation of Gene Expression

A region of eukaryotic DNA consists of over fifty repeats of the same sequence of twelve bases. Where is this repetitive region least likely to be found?

• An exon

• An intron

• A polymerase binding site

• Satellite DNA

Which feature distinguishes eukaryotic genomes from prokaryotic genomes?

• Eukaryotic genomes contain non-coding sequences called introns.

• Eukaryotic genomes contain no short repetitive sequences of DNA.

• Eukaryotic genomes have genes aggregated into operons.

• Eukaryotic genomes possess plasmids.

What describes common features of the telomere and the centromere?

• Both areas have proteins associated with them.

• Both are made of DNA with high incidence of adenine and thymine.

• Both DNA sequences are conserved throughout the life of an organism.

• During interphase, DNA replication takes place simultaneously in both regions.

The small sequence of 11 base pairs shown in the diagram is conserved in the DNA of chromosome centromeres in all species. Mutations within the underlined triplet inactivate the centromere.

-T-G-A-T-T-T-C-C-G-A-A-

-A-C-T-A-A-A-G-G-C-T-T-

What is the function of this DNA sequence?

• It codes for a spindle.

• It is non-coding, but provides an attachment site for a spindle protein.

• It codes for RNA.

• It distinguishes one chromosome from another.

Tags

NGSS.HS-LS1-4

Which of the following is characteristic of genes and gene regulation in both bacteria and eukaryotes?

• Promoter

• Non-coding DNA with coding sequences

• Enhancer

• DNA located in a nucleus

Which type of control of gene expression is commonly found in both prokaryotes and eukaryotes?

• post transcriptional

• post translational

• transcriptional

• translational

Through differential mRNA processing, eukaryotes

• reinforce gene inactivation

• produce related but different proteins in different tissues

• amplify genes to meet the requirement of high levels of a gene product

• bind transcription factors to enhancers to activate transcription

Which row in the table identifies the regions of the molecule of a eukaryotic primary mRNA where methyl-G capping and poly(A) tailing may occur?

• Row A

• Row B

• Row C

• Row D

The processing of pre-mRNA involves the following steps to produce functional mRNA,

1. Polyadenylation

2. Remove of introns

3. Splicing of exons

4. Capping

In which order do they occur?

• 1, 3, 2, 4

• 2, 4, 1, 3

• 3, 1, 4, 2

• 4, 2, 3, 1

What is an example of translational control of gene expression?

• activation of proteins by folding or enzymatic cleavage

• addition of chemical groups, such as phosphate groups, to free amino acids in the cytoplasm

• binding of protein factors to specific sequence in mRNA preventing ribosomes attaching

• formation of disulfide bridges in the protein being formed