BIO 111 Lecture Notes - Lecture 14: Missense Mutation, Frameshift Mutation, Nonsense Mutation
Document Summary
Point mutation: affects only one base pair. 2 basic alterations: change base sequence, add or remove nucleotides. Changes a single amino acid in polypeptide. Addiction or deletion of nucleotides that are not multiples of 3. May alter the sequence within a promoter. Somatic cells are all other body cells. Spontaneous mutations result from abnormalities in biological processes. Induced mutations are brought on by environmental agents. Mutation rate higher than spontaneous mutation rate. Altered dna strand removed and new segment synthesized. Mutations that cause genetic changes (ex: uv light) Dna alterations effects on gene expression that affect cell division, lead to cancer. Mutation causes this gene to be overactive. Cyclins; responsible for advancing a cell through the 4 phases of the cell cycle. Ex) p53 gene is active when dna is damaged. Cell cant progress from g1 to s phase. Mutations can cause the proto-o(cid:374)(cid:272)oge(cid:374)e to (cid:271)e(cid:272)o(cid:373)e a(cid:374) (cid:862)o(cid:374)(cid:272)oge(cid:374)e(cid:863) o(cid:396) (cid:272)a(cid:374)(cid:272)e(cid:396) p(cid:396)o(cid:373)oti(cid:374)g ge(cid:374)e.
