Genetic Mutations and Molecular Biology

These flashcards cover essential concepts related to genetic mutations, molecular biology, and the processes of transcription and translation.

What are codons?

Three nucleotide triplets in mRNA that code for amino acids.

What is a frameshift mutation?

A genetic mutation caused by insertion or deletion of nucleotides that shifts the reading frame.

What is a nonsense mutation?

A mutation that converts a codon for an amino acid into a stop codon.

What is a missense mutation?

A mutation that changes one amino acid in a protein to another.

What is a silent mutation?

A mutation that changes a codon but does not change the amino acid it codes for.

What causes a frameshift mutation?

Insertion or deletion of nucleotides not in multiples of three.

What is the central dogma of molecular biology?

The flow of genetic information from DNA to mRNA to protein.

How many hydrogen bonds form between cytosine and guanine?

Three hydrogen bonds.

What is the difference between somatic cells and germline cells?

Somatic cells are all body cells except germline cells which give rise to gametes.

What is RNA processing?

The modification of mRNA before it is exported from the nucleus, including capping, polyadenylation, and splicing.

What are the three components of a nucleotide?

A phosphate group, a five-carbon sugar, and a nitrogenous base.

What is the function of the spliceosome?

To carry out the splicing of introns from mRNA.

What enzyme is responsible for charging tRNA with amino acids?

Aminoacyl-tRNA synthetase.

What does it mean for the genetic code to be redundant?

More than one codon can code for the same amino acid.

Where does translation occur in eukaryotic cells?

In the cytosol or on the rough endoplasmic reticulum.

What is the role of the TATA box?

A component of the promoter that helps determine which strand is the template strand and the direction of transcription.

What happens during translation initiation?

The small ribosomal subunit binds to the mRNA and the initiator tRNA binds at the P site.

What is alternative splicing?

The process by which different combinations of exons are joined to create multiple protein products from a single gene.

What is the significance of the GC content in DNA?

Higher GC content requires more heat to denature the DNA due to the presence of three hydrogen bonds between C and G.

How are ribosomes targeted to the rough ER?

They have a signal peptide recognized by the signal recognition particle (SRP).