ap biology 2/18
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'.
Which of the following help(s) to stabilize mRNA by inhibiting its degradation?
5' cap and poly (A) tail
If a template DNA strand has base sequence: 3′-GTC...CCA-5′, what would be the sequence of the corresponding mRNA? [Note: "..." represents an intervening sequence.]
5'-CAG...GGU-3'
The direction of synthesis for a new mRNA molecule is _______ from a _______ template strand.
5¢-to-3¢; 3¢-to-5¢
central dogma
DNA -> RNA -> Protein (polypeptide)
Which of the following statements about the flow of genetic information is true?
DNA encodes information that is translated into RNA, and RNA encodes information that is translated into proteins.
Which of the following is not required for transcription?
DNA polymerase
Which component of transcribed RNA in eukaryotes is present in the primary transcript but is removed before translation occurs?
Intron
Which of the following statements about pre-mRNA splicing is false?
It is common in prokaryotes.
Which of the following discoveries caused the modification of the "one gene-one protein" hypothesis to the "one gene-one polypeptide" hypothesis?
Proteins made up of two or more chains
Using RNA as a template for protein synthesis instead of translating proteins directly from the DNA is advantageous for the cell because
RNA acts as an expendable copy of the genetic material.
RNA polymerases differ from DNA polymerases in that
RNA polymerases are less effective at proofreading than DNA polymerases.
In an experimental situation, a student researcher inserts an mRNA molecule into a eukaryotic cell after he has removed its 5' cap and poly(A) tail. Which of the following would you expect him to find?
The molecule is digested by exonucleases since it is no longer protected at the 5' end.
Which of the following is (are) true of snRNPs?
They join together to form a large structure called the spliceosome.
Transcription is the process by which
an RNA molecule is synthesized from a DNA template.
What is a ribozyme?
an RNA with enzymatic activity
translation is...
base to amino acid
transciption is...
base to base
what does translation do?
converts mRNA (base) sequence to amino acid sequence of a polypeptide
what does transcription do?
copies information from a DNA sequence (a gene) to a complementary RNA sequence
Once transcribed, eukaryotic mRNA typically undergoes substantial alteration that includes
excision of introns.
What are the coding segments of a stretch of eukaryotic DNA called?
exons
When eukaryotic DNA is hybridized with mRNA, the hybrid molecules contain loops of double-stranded DNA called
introns
Which of the following molecules is most involved in the transfer of genetic information from the nucleus to the cytoplasm?
mRNA
Promoters are made of
nucleic acids.
garrod correlated what?
one gene to one enzyme
what was garrods hypothesis revised to?
one gene to one polypeptide relationship
During initiation, the sequence of DNA to which RNA polymerase binds most tightly is the
promoter
RNA polymerase is a
protein
Transcription in eukaryotes requires which of the following in addition to RNA polymerase?
several transcription factors (TFs)
In eukaryotes, exons are
spliced together from the original transcript.
Which of the following molecules transfers information from mRNA to protein?
tRNA
Termination of transcription involves a
terminator sequence.
Introns are significant to biological evolution because
their presence allows exons to be shuffled.
The "adapters" that allow translation of the four-letter nucleic acid language into the 20-letter protein language are called
transfer RNAs.
The process by which information in the nucleic acid sequence is used to direct the production of a specific chain of amino acids is called
translation
The transcription initiation site is located
within the promoter.
