DNA Structure
What is the shape of DNA?
A double helix.
Which enzyme "unzips" the DNA strands?
DNA helicase
What is the process of making RNA from DNA?
Transcription.
What is an operon?
A group of genes controlled together by one switch (operator).
What tool is used to cut DNA at specific sites?
Restriction enzymes.
What are the building blocks of DNA?
Nucleotides.
Which enzyme adds complementary nucleotides during DNA replication?
DNA polymerase.
Which RNA carries the genetic code to the ribosome?
mRNA (messenger RNA).
What does the lac operon regulate?
Helps bacteria break down lactose for energy.
What is the purpose of PCR?
To amplify DNA.
Which nitrogenous base pairs with cytosine in DNA?
Guanine.
What is the difference between the leading and lagging strand?
The leading strand is synthesized continuously, while the lagging strand is synthesized in fragments.
What is the process of converting mRNA into a protein?
Translation
What happens to the lac operon when lactose is absent?
The repressor binds to the operator, blocking transcription.
What is the role of a plasmid in genetic engineering?
It acts as a vector to insert foreign genes into bacteria.
What are the components of a nucleotide?
A sugar, a phosphate group, and a nitrogenous base.
What are the small fragments synthesized on the lagging strand called?
Okazaki fragments.
What is the role of tRNA in translation?
It brings amino acids to the ribosome and matches them to the codons on mRNA.
What is the role of tryptophan in the trp operon?
It acts as a corepressor that activates the repressor protein.
What technique is used to separate DNA fragments by size?
Gel electrophoresis.
Which carbon in the sugar determines the direction of the DNA strand (5' to 3')?
The 5' and 3' carbons and Promoter sequence
What prevents the DNA strands from rejoining during replication?
Single-strand binding proteins (SSBs).
What are the three binding sites for tRNA on the ribosome?
A site, P site, and E site.
How do inducible and repressible operons differ?
Inducible operons are activated by a substrate, while repressible operons are turned off by the end product.
What does CRISPR-Cas9 do?
It edits DNA by cutting at specific sequences and allowing for modification.