Ch 17 CHS Test Transcription

Adenine, a nitrogenous base is found in which group of compounds?

• fatty acids. lipids and hormones

• proteins, ATP & DNA

• glucose, ATP, & GTP

• ATP, DNA, & RNA

If you have a triplet code of DNA that is 5'-ACG-3' , what is the corresponding codon in mRNA?

• 5'-TGC-3'

• 3'-UGC-5'

• 3'-TGC-5'

• 5'-UGC-3'

Which best describes termination in transcription?

• RNA polymerase transcribes through the poly A tail causing RNA polymerase to be released.

• RNA polymerase transcribe through the terminator sequence AAUAAA causing RNA polymerase to be released.

• RNA polymerase transcribes through an intron which causes RNA polymerase to be released.

• RNA polymerase transcribes until it reaches the telomeres at the end of an entire chromosome.

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

• The protein product of the promotor.

• Start and stop anticodons

• Transcription factors

• ribosomes and tRNA

A eukaryotic transcription unit may be over 8,000 nucleotides long. However only 1,200 nucleotides may be used to make a protein that is only 300 amino acids long. How is this best explained?

• There is ambiguity in the genetic code as well as redundancy.

• There are several noncoding stretches of nucleotides that are regulatory such as the promotor region.

• Numerous nucleotides are needed to code for each amino acids

• Nucleotids break off and are lost during transcription.

Alternative DNA splicing allows for. . .

• increasing the rate of transcription.

• the production of proteins of different sizes and thus functions from a single mRNA.

• producing identical copies of the same protein in mass.

• increasing the rate of translation.

A graduate student is doing research where she needs to insert mRNA into a eukaryotic cell. She forgets to put on a 5' Guanine cap. What will most likely occur?

• The mRNA could not exit the nucleus to be translated at the Golgi complex.

• The cell recognizes the absences of the tail and polyadenlyates the mRNA.

• The molecule is digested by restriction enzymes in the nucleus.

• The molecule is digested by exonucleases in the cytoplasm since it is no longer protected at the 5' end.

Given the following primary transcript:

5'-UTRE₁I₁E₂I₂E₃I₃E₄UTR-3'

where E stands for exon and I stand for intron.

What will be found in the cytoplasm?

• 5'-UTRE₁I₁E₂I₂E₃I₃E₄UTR-3'

• 5'-UTRE₁E₂E₃ E₄UTR-3'

• 5'-UTRE₁I₁E₂I₂ I₃ UTR-3'

• 5'-UTR I₁ I₂ I₃ UTR-3'

If a mutation occurs that removes most of the 5'end of the 5' UTR what is the most likely result?

• No effect because the exons are maintained.

• The mRNA degrades because there would be no 5' Guanine cap to protect it from enzymes in the cytosol.

• The 3' UTR will duplicate itself and replace the 5' UTR.

• The first exon will not be read because Intron 1 will now serve as the UTR at the 5' end.

In eukaryotic cells, transcription cannot begin until . . .

• several transcription factors have bound to the promoter region on the DNA.

• the entire DNA double helix is unwound completely along the chromosome.

• the 5' Guanine caps are removed from the mRNA.

• the DNA exons are removed from the template.