Practice Flashcards
If the gene for primase were mutated so that no functional primase was produced, would polymerization of DNA still occur in Rolling-circle replication?
Consider a eukaryotic cell. How would the concentrations of H1, H2A, and H3 histones differ?
1 H1, 2 of all other ones
What characteristics are exhibited by a cytoplasmically inherited trait?
-encoded by genes in the cytoplasm.
-Because the cytoplasm usually is inherited from a single (most often the female) parent, reciprocal crosses do not show the same results.
-Often show great variability because different egg cells (female gametes) may have differing proportions of cytoplasmic alleles from random sorting of mitochondria (or plastids in plants).
What synthesizes the leading strand in prokaryotes:
DNAP III
What is the end of replication problem?
The ends of these chromosomes cannot be fully copied during replication because of the lack of 3’-OH group for replacement nucleotides
What would be the effect on DNA replication of mutations that destroyed 5’–> 3’ exonuclease activity?
bwill digest nucleotides in the 5´ to 3´ direction on a template ahead of polymerase activity so they can be corrected
What are a major requirements of DNA replication?
Following transcription, pre-mRNA contains:
Over evolutionary time, DNA replaced RNA as the primary carrier of genetic information, and the chemical stability of DNA is believed to be the key reason for this. Which attribute of DNA is the reason behind its chemical stability?
DNA is double-stranded throughout its length, while RNA is predominantly single-stranded.
DNA lacks the hydroxyl group on the 2’ carbon, making it more chemically stable.
The C-H bonds in DNA contribute to its stability.
Which of the following is NOT required for transcription?
A mutation produces a nonfunctional sigma factor, RNA polymerase will:
Not initiate transcription
Lariats are composed of:
2′-5′ phosphodiester bond between a bulged adenosine and the 5′ end of the intron.
Alternative splice sites result in different:
mRNA transcripts
The 5′ and 3′ untranslated regions (UTRs) of processed mRNA molecules are derived from:
What is the correct order for the process of pre-mRNA splicing in nuclear genes? (First step to last step)
-5’ cap is added
-3’ poly-A tail is added to the end.
-splicing, some sections of the RNA transcript (introns) are removed, and the remaining sections (exons) are stuck back together
-Alternative splicing
Which of the following statements regarding gene structure is TRUE?
A mutation introduces more genetic material within an intron, which of the following best describes the effect this mutation will have on the encoded protein?
