DNA & RNA Notes Flashcards
What is the Central Dogma of molecular biology?
The Central Dogma describes the flow of genetic information from DNA to RNA to protein.
The processes involved are replication, transcription, and translation.
What is the first process in the Central Dogma?
Replication
What is the second process in the Central Dogma?
Transcription
What is the third process in the Central Dogma?
Translation
What occurs during DNA replication?
The DNA double-helix opens up, free-floating nucleotides line up with their partners, and two identical DNA helices are created.
What is the role of DNA helicase in DNA replication?
DNA helicase opens up the DNA to be replicated.
During which phase does DNA replication occur?
Interphase
What types of nucleotides are present in RNA?
Adenine (A), Uracil (U), Guanine (G), Cytosine (C)
What is the function of mRNA?
mRNA serves as a messenger carrying the genetic information from DNA to the ribosome.
What is the function of tRNA?
tRNA transports amino acids to the ribosome.
What is the function of rRNA?
rRNA is a structural component of ribosomes, facilitating translation.
What is the first step in transcription?
A small section of DNA is opened up.
In transcription, what does the DNA strand act as?
A template for mRNA synthesis.
What initiates the translation process?
The mRNA strand connects to the ribosome.
What is a codon?
A sequence of three nucleotides in mRNA that codes for a specific amino acid.
What is a stop codon?
UAG, UAA, or UGA, which signals the end of translation.
What are mutations?
Mistakes or errors in DNA replication that result in changes to the hereditary material.
What can cause mutations?
Exposure to chemicals or environmental conditions.
What is a gene mutation?
A change in the base sequence of a gene.
What is a point mutation?
A single base substitution.
What is a silent mutation?
A mutation that does not change the amino acid sequence.
What is a nonsense mutation?
A mutation that results in a stop codon, truncating the protein.
What is a missense mutation?
A mutation that changes a codon to specify a different amino acid.
What is a deletion mutation?
A mutation where one or more base pairs are lost from the DNA.
What is an insertion mutation?
A mutation where additional base pairs are added to the DNA sequence.
What is a genetic disorder?
An abnormal condition inherited from parents, often resulting from mutations.
Give an example of a genetic disorder caused by a single gene mutation.
Cystic fibrosis, hemophilia, or sickle cell disease.
What is Down syndrome?
A genetic disorder caused by having an extra copy of chromosome 21.
True or False: Mutations are inherently bad.
False. Mutations can change the survivability of an organism.
What is the role of amino acids in protein synthesis?
Amino acids are the building blocks of proteins, with each codon in mRNA corresponding to one amino acid.
