Mutations and DNA Repair Mechanisms

These flashcards cover key concepts related to mutations, DNA repair mechanisms, and gene transfer, aiding in the understanding and retention of the topics discussed in the lecture.

Mutation

A change in the DNA sequence that can lead to alterations in gene function.

Point Mutation

A mutation that involves a change in a single nucleotide base pair in DNA.

Silent Mutation

A mutation that does not change the amino acid sequence of a protein.

Missense Mutation

A mutation that causes a change in one amino acid in a protein sequence.

Nonsense Mutation

A mutation that introduces a premature stop codon in the sequence, leading to incomplete proteins.

Frameshift Mutation

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

Mutagen

An agent, such as radiation or a chemical, that causes genetic mutation.

Excision Repair

A precise DNA repair mechanism that removes damaged or mismatched bases and replaces them.

SOS Response

A DNA repair mechanism activated in response to significant DNA damage.

Horizontal Gene Transfer

The movement of genetic material between organisms, as seen in transformation, transduction, and conjugation.

Transformation

The uptake of free DNA from the environment by a bacterial cell.

Transduction

The transfer of DNA from one bacterium to another by a virus.

Conjugation

A process by which one bacterium transfers genetic material to another through direct contact.

Vertical Gene Transfer

The transmission of genetic material from parent to offspring.

Thymine Dimer

A DNA lesion formed when two adjacent thymine bases bond improperly due to UV radiation.