Genetic Structure
The shape of a DNA/RNA molecule.
What is a helix?
Changes in an organism's genes are referred to as __
What is a mutation?
The enzyme responsible for unwinding DNA.
What is DNA helicase?
In the lac operon, this sugar inactivates the repressor, allowing transcription to proceed.
This is only direction DNA polymerase can add nucleotides.
What is the 5' to 3' direction?
The nucleotide base that is only present in RNA.
What is uracil?
A mutation with the lowest chance of a harmful result
What is a silent mutation?
The enzyme that joins the Okazaki fragments on the lagging strand
What is DNA ligase?
In prokaryotes, this cluster of genes is transcribed together under the control of a single promoter and operator.
What is an operon?
This three-nucleotide sequence on mRNA specifies a particular amino acid during translation.
What is a codon?
The Meselson-Stahl experiment proves this vision of DNA replication
What is the semi-conservative model?
Two methods with which sexual reproduction creates genetic variation
What is crossing over in meiosis, independent assortment, and/or random gametes?
The enzyme that lays down primers to mark where DNA polymerase starts
RNA primase
This type of regulatory protein increases gene transcription by helping RNA polymerase bind to DNA.
What is an activator?
This molecule carries amino acids to the ribosome during translation.
What is tRNA?
An extrachromosal, double-stranded, circular DNA molecule that exists in both prokaryotes and eukaryotes
External factors that increase the chances of mutations
What are mutagens? (radiation, chemicals, viruses)
The enzyme that relaxes the supercoil pressure at the replication fork
What is topoisomerase?
In eukaryotic cells, this structure separates transcription from translation, allowing for additional regulation steps.
What is the nucleus?
A function of the 5' cap on the end of a mRNA molecule.
What is preventing mRNA degradation/making ribosome binding easier?
Adenine and guanine both share this classification
What is a purine?
The absorption of viral DNA
The direction that RNA polymerase builds in during the elongation period of DNA transcription.
What is the 3' direction?
This process modifies pre-mRNA by removing introns and joining exons, allowing for multiple proteins from one gene.
What is RNA splicing?
This enzyme adds adenine nucleotides to form the poly-A tail.
What is poly-A-polymerase?