Module 2 Practice Exam and Review Flashcards
What are the 3 classes of “functional” (non-mRNA) RNAs? Briefly describe the role of each class of functional RNA.
tRNA: brings the correct amino acid to the mRNA during translation
rRNA: major component of ribosomes
snRNA: helps process RNA transcripts (especially, helps remove introns).
- Messenger RNA: contains blueprint for protein synthesis
- Transfer RNA: brings correct amino acid to the ribosome
- Ribosomal RNA: makes ribosomes
Here is a list of eukaryotic RNA polymerases. Match them with what they transcribe.
RNA Pol I; RNA Pol II; RNA Pol III
mRNA, tRNA, rRNA, snRNA
?? RESEARCH THIS!!
RNA Pol I: rRNA
RNA Pol II: snRNA, mRNA
RNA Pol III: tRNA
continuous synthesis
leading strand
theta replication
bidirectional circular replication
In the Meselson-Stahl experiment, what hypothetical form of DNA replication results in the same DNA density distribution as the semiconservative method after the first cell division, but was not supported upon the second cell division?
??
dispersive replication?
Eukaryotes have two of these per chromatid; prokaryotes have none.
telomeres
In eukaryotes, tRNAs are
transcribed in the nucleus, but function in the cytoplasm.
As a ribosome translocates along an mRNA molecule by one codon, which of the following occurs?
The tRNA that was in the A site moves into the P site.
Transcription of the sequence AATGCGGTC would result in
UUACGCCAG
What is a gene?
A sequence of DNA that encodes a protein
Telomeres________________the end of chromosomes
stabilize
Which is true of the secondary structure of DNA?
Bases on complementary strands are held together by hydrogen bonds.
What is semiconservative replication?
??!!!!
Replication in which each of the original nucleotide strands remains intact, despite no longer being combined in the same molecule. The original DNA molecule is half conserved during replication. Each strand serves as a template for synthesis of a new strand. Production of two identical double strands of DNA consisting of one new strand and one original strand.
A friend gave you the following molecule and told you that it was a fragment of his RNA. Do you believe him? Justify your answer.
No, the molecule has T’s. If it were truly RNA, it would have U’s (Uracil) rather than T’s
An organism has a G content of 17%. What is the percentage for A?
33%
This molecule is synthesized using nucleotides containing the bases adenine, guanine, cytosine, and uracil.
RNA only
This enzyme links two separate lengths of nucleic acid by creating a phosphodiester bond between them.
DNA ligase
RNA polymerase II binds to the ____________ strand of DNA and uses it to guide transcription. In contrast, the strand not used to guide transcription is called the _____________ .
??!!!
leading, lagging?
Which of the following statements about the genetic code are TRUE?
Most amino acids are encoded by more than one codon
What chemical group is found at the 3’ end of a DNA molecule?
hydroxyl group
The nitrogenous base that is found in RNA but not in DNA is
uracil
What is the function of eukaryotic RNA polymerase I?
transcription of rRNA genes
Hairpins are formed in DNA as a result of
sequences on the same strand that are inverted and complementary
Translation of RNA into protein takes place on which cellular organelle?
Ribosome