Quiz 3 Flashcards
Which of the following is true about the central dogma?
none of the above
DNA -> Protein -> RNA
Protein -> RNA -> DNA
RNA -> DNA -> Protein
none of the above
Which of the following is not a component of a nucleotide?
phosphate
deoxyribose
phosphodiester
nitrogenous base
phosphodiester
Which of the following is not true about the structure of DNA?
the most commonly found DNA conformation is B-DNA
double-stranded DNA has both a sense and antisense strand
guanine and cytosine bond with 2 hydrogen bonds while adenine and thymine bond with 3 hydrogen bonds
DNA is a right-handed (clockwise) double-helix
guanine and cytosine bond with 2 hydrogen bonds while adenine and thymine bond with 3 hydrogen bonds
What is not true about DNA and RNA?
thymine is present in both DNA and RNA
DNA is more stable than RNA
DNA is used as a genetic storage while RNA can perform various roles in a cell
RNA is typically single stranded and DNA is typically double stranded
thymine is present in both DNA and RNA
What is the purpose of the 3’- poly A tail?
it carries amino acids from the cytoplasm to the ribosome
it is an essential component of ribosomes
none of the above
it improves the stability of the mRNA and facilitates its export from the nucleus
it improves the stability of the mRNA and facilitates its export from the nucleus
Which of the following is a step in DNA replication?
termination
all of the above
elongation
initiation
all of the above
What is the role of helicase in DNA replication?
unwind the DNA helix by breaking the hydrogen bonds between nitrogenous bases
bind to single-stranded DNA to avoid DNA rewinding back
synthesize RNA primers needed to start replication
seal the gaps between Okazaki fragments
unwind the DNA helix by breaking the hydrogen bonds between nitrogenous bases
Which of the following is not a characteristic of replisomes?
only carries out replication of the leading strand
carries out the replication of both the leading and lagging strand
a complex that carries out replication of DNA and is composed of 3 DNA polymerases
it synthesizes DNA in the 5’ to 3’ direction
only carries out replication of the leading strand
What is the difference between leading and lagging strand synthesis?
leading strand synthesis uses primase while lagging strand synthesis does not use primase
leading strand synthesis includes the placement of Okazaki fragments while lagging strand synthesis is continuous
leading strand synthesis does not use primase while lagging strand synthesis does use primase
leading strand synthesis is continuous while lagging strand synthesis includes the placement of Okazaki fragments
leading strand synthesis is continuous while lagging strand synthesis includes the placement of Okazaki fragments
Which of the following is not true about DNA replication?
replication is semi-conservative
replication is bidirectional only in prokaryotes
prokaryotic cells have one origin of replication
eukaryotic cells have multiple origins of replication
replication is bidirectional only in prokaryotes
