Chapter 15.1.2 (Exam 4) Mutations Flashcards
Mutations Are Heritable Changes in DNA (9 cards)
What are point mutations?
Insertion or deletion of a single base pair, or substitution of one base pair for another
What are the two types of substitutions?
Transition
Transversion
What is a transition point mutation?
Purine to Purine (A to G, G to A)
Pyrimidine to Pyrimidine (T to C, C to T)
What is a transversion point mutation?
Purine to Pyrimidine (A to T, A to C, G to T, G to C)
Pyrimidine to Purine (T to A, T to G, C to A, C to G)
What are silent mutations?
A nucleotide base change in a codon that does not change the amino acid it codes for
The result is no difference in the translated protein
What is a missense mutation?
A nucleotide base change in a codon that changes the amino acid it codes for
The result is a difference in the translated protein
What is a nonsense mutation?
A nucleotide base change in a codon that changes the amino acid it codes for into a stop codon
The result is a difference in the translated protein, it’s generally shortened and nonfunctional
What is a loss of stop mutation?
A nucleotide base change in a codon that changes the stop codon it codes for into an amino acid
The result is a difference in the translated protein, it’s generally longer and nonfunctional
What is a frame-shift mutation?
An insertion or deletion results in every downstream codon being shifted
The result is a difference in the translated protein, it’s generally nonfunctional and can be longer or shorter
