AP Biology DNA RNA and Protein Synthesis

What is the corresponding codon for AGT?

• UCA
• TCA
• UGA
• ACU

Which description of nucleotide triplets best represents a codon?

• a triplet separated spatially from other triplets
• a triplet that has no corresponding amino acid
• a sequence of tRNA at the 3' end
• a triplet in the same reading frame as an upstream AUG

Which of the following does not occur in prokaryotic gene expression but does occur in eukaryotic gene expression?

• mRNA, tRNA, and rRNA are transcribed
• RNA polymerase binds to the promotor
• a poly-A tail is added to the ends of the mRNA
• Transcription can begin as soon as translation has begun even alittle

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

• the protein  product of the promotor
• start and stop codons
• ribosomes and tRNA
• several transcription factors

Which of the follwoing best describes the significance of the TATA box in eukaryotic promoters?

• it is the recognition site for a specific transcription factor
• it sets the reading frame of the mRNA
• it is the recognition site for ribosomal binding
• it signals the end of the nucleotide sequence of the gene

RNA polymerase moves in which direction along the DNA?

• 5' to 3' 
• 3' to 5' along the template strand
• 3' to 5' along nontemplate(coding) strand
• 5' to 3' along the template strand

What is the function of the poly-A tail in mRNA?

• to add modified guanin to the 3' end of the mRNA
• to indicate the site of translational termination
• to code for the binding of RNA polymerase to the DNA
• to help protect the mRNA from degradation by hydrolytic enzymes 

What is a ribozyme?

• enzyme that uses RNA as a substrate
• RNA with enzymatic activity
• an enzyme that catlyzes the association between the large and small ribosomal subunits
• an enzyme tha synthesizes RNA primers during DNA replication

When  the spliceosome binds to a pre-mRNA transcript, where does it  typically attach?

• to the exons
• to the 5'UTR
• to the 3'UTR
• at certain sequences along an intron

What is the anticodon on the tRNA that binds to mRNA codon for the DNA coding sequence AAA?

• TTT
• UUU
• UUA
• AAA