d1.3

Flashcards based on key concepts of gene mutations and gene editing techniques.

What is a gene mutation?

A change in the sequence of base pairs in a DNA molecule; this may result in a new allele.

What types of mutations can affect gene function?

Substitution, insertion, and deletion mutations.

What is a substitution mutation?

A mutation where a nucleotide base in the DNA sequence is randomly swapped for a different base.

What is an insertion mutation?

A mutation that occurs when a nucleotide with a new base is randomly inserted into the DNA sequence.

What is a deletion mutation?

A mutation that occurs when a nucleotide is randomly deleted from the DNA sequence.

What is a frameshift mutation?

A mutation that results from insertions or deletions, changing the reading frame of the nucleotide sequence.

What are mutagenic agents?

Environmental factors that increase the mutation rate of cells.

What is a single nucleotide polymorphism (SNP)?

A substitution mutation that represents a difference in a single DNA nucleotide.

What are silent mutations?

Mutations that do not alter the amino acid sequence of the polypeptide.

What are missense mutations?

Mutations that alter a single amino acid in the polypeptide chain.

What are nonsense mutations?

Mutations that create a premature stop codon, leading to an incomplete polypeptide chain.

How do mutations in somatic cells differ from mutations in germ cells?

Somatic cell mutations are not inherited, while germ cell mutations can be passed to offspring.

What is the role of the Human Genome Project?

To determine the DNA sequence of the entire human genome and record every gene.

What is gene knockout?

A technique where a gene is removed or made unusable to study its function.

What is CRISPR?

A gene editing technique that allows scientists to alter DNA at specific sites in the genome.

Why are insertions and deletions often considered more harmful than substitutions?

They can disrupt the reading frame of the genetic code, leading to a complete change in the protein produced.