Replication, Transcription and Translation
What does DNA Helicase do in the replication fork?
Unzips/unwinds the DNA strands
What kind of mutation changes a normal codon into a stop codon?
nonsense
What is an Operon?
Genes that are grouped together with similar functions.
What are two ways that pre-mRNA is processed?
Possible Answers: 5' cap, Poly A tail, removal of introns, alternative RNA splicing
What two bases are purines?
Adenine and guanine
DNA is placed on the positive end, moves toward the negative end, separated by length
Gel electrophoresis
Describe the function of mRNA.
Carries genetic info from DNA to ribosomes and acts as a template for protein synthesis.
how do mutations contribute to genetic variation?
mutations introduce new alleles that can change the phenotype of an organism, potentially increasing its fitness.
Describe two epigenetic modifications and their impacts on gene expression.
DNA methylation: decreases expression
Histone Acetylation: increases expression
What components make up the translation initiation complex?
mRNA, Ribosomal subunits, and initiation factors
Name two differences between DNA and RNA structure.
DNA is double stranded, RNA is single, DNA has T RNA has U, or DNA has deoxyribose sugar and RNA ribose.
Explain how gene regulation impacts cell specialization.
Controls what genes are turned on or off which impacts phenotype and function.
Explain the difference between DNA Polymerase I and III.
III adds nucleotides to chain, while I replaces RNA nucleotides of primer with DNA.
Explain what plasmids are.
Plasmids are small circular DNA molecules that can be found in both prokaryotes and eukaryotes.
Explain two differences between an inducible and repressible operon.
Induciblle: Naturally turned off; catabolic pathways Repressible: Naturally turned on; anabolic