• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

Card Range To Study



Play button


Play button




Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

32 Cards in this Set

  • Front
  • Back
Pyrimidines: define and list
contain 1 carbon-nitrogen ring
C and T
Pyrimidines: define and list
contain 1 carbon-nitrogen ring
C and T
Purines: define and list
contain double carbon ring
A and G
What is the purpose of DNA helicase
to unwind the double helix
What is the purpose of DNA topoisomerase?
to remove supercoils
What is the direction of DNA replication? (synthesis)
synthesize 5'-->3'
What is the purpose of DnaA protein in prokaryotic replication?
melts AT-rich consensus sequence at origin to separate DNA (requires ATP)
What is the purpose of the alpha subunit of DNA polymerase III?
primase (makes primer)
5'-->3' polymerase activity
What is the purpose of the delta subunit of DNA polymerase III?
completes synthesis
3'-->5' exonuclease activity (proofreads)
What is the purpose of the beta and epsilon subunit of DNA polymerase III?
exonuclease activity (proofreads); also involved in repair
What is the purpose of pol gamma? (the eukaryotic DNA polymerase)
replicates mitochondrial DNA
What is the purpose(2) of telomerase? How does it work?
(1) Replaces primer on 5' lagging strand. (2) Provide end stability Adds TG-rich "telomeres" to extend the 3' end using CG-rich template
What is the purpose/result of reverse transcriptase?
RNA-->DNA using RNA directed polymerases
What are transposons?
DNA elements that can insert and move about the genome
What is allelic heterogeneity?
different mutations at the same locus cause the same disorder
What is phenocopy?
an individual whose phenotype, under a particular environmental condition, is identical to the one of another individual whose phenotype is determined by the genotype
What is locus heterogeneity?
genetic conditions where a single syndrome is caused by different genes in different families, possibly due to the different environmental factors that have influenced them
What is homologous recombination?
a type of genetic recombination in which nucleotide sequences are exchanged between two similar or identical molecules of DNA
What is a sigma factor (σ factor)?
a prokaryotic transcription initiation factor that enables specific binding of RNA polymerase to gene promoters
What are snRNPs (small nuclear ribonucleoproteins)?
RNA-protein complexes that combine with unmodified pre-mRNA and various other proteins to form a spliceosome, a large RNA-protein molecular complex upon which splicing of pre-mRNA occurs
What is TFIID? What does it do?
one of several general transcription factors that make up the RNA polymerase II preinitiation complex. Before the start of transcription, the transcription Factor II D (TFIID) complex, consisting of TFIID, TBP, and at least nine other polypeptides, binds to the TATA box in the core promoter of the gene.
What is TFIIA? What does it do?
specifically required for transcription of 5S rRNA genes and is the archetypal C2H2 zinc finger protein
What are DNA polymerase I's enzymatic activities?
(1) 5' -> 3' DNA polymerase activity (2) 3' -> 5' exonuclease activity that mediates proofreading (3) 5' -> 3' exonuclease activity mediating nick translation during DNA repair
define/describe DNA polymerase II
most likely involved in DNA repair; lacks a 5'->3' exonuclease activity
What are the subunits of DNA polymerase III and their purposes?
the α subunit has polymerization activity.
the ε subunit has proofreading activity.
the θ subunit stimulates the ε subunit's proofreading.
What is the signal hypothesis?
The major mechanism whereby proteins that insert into or cross a membrane are synthesized by a membrane-bound ribosome. The first thirteen to thirty-six amino acids synthesized, termed a signal peptide, are recognized by a signal recognition particle that draws the ribosome to the membrane surface by interaction with a docking protein. The signal peptide may later be removed from the protein.
What does RNA polymerase I transcribe?
What does RNA polymerase II transcribe?
precursors of mRNA and most snRNA and microRNA
What does RNA polymerase III transcribe?
ribosomal 5S rRNA, tRNA and other small RNAs
Define haplo-insufficiency
when a diploid organism only has a single functional copy of a gene and the single functional copy of the gene does not produce enough of a gene product
Define transversion mutation.
the substitution of a purine for a pyrimidine or vice versa
Define transition mutation.
a point mutation that changes a purine nucleotide to another purine or a pyrimidine nucleotide to another pyrimidine.