Bio Unit 9: When Good Cells Go Bad

missense mutation

A base-pair substitution that results in a codon that codes for a different amino acid.

nonsense mutation

A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.

silent mutation

A mutation that changes a single nucleotide, but does not change the amino acid created.

frameshift mutation

involves the insertion or deletion of a nucleotide in the DNA sequence

cancer

can develop when the cell cycle is not regulated

tumor suppressor genes

genes that stop cell division and kill cells that have too many mutations

Proto-oncogenes

genes that are responsible for normal cell growth and division

Apoptosis

programmed cell death that prevents bad cells from making copies of themselves

substitution mutation

A single nucleotide is replaced by a different nucleotide

insertion mutation

a mutation in which one or more nucleotides are added to a gene

deletion mutation

a mutation in which one or more pairs of nucleotides are removed from a gene

cell cycle checkpoints

systems that monitor cells as they progress through various cell cycle stages

G0 Checkpoint

if conditions are not appropriate for the cell to divide or if it is not programmed to divide they are in this phase

point mutation

gene mutation in which a single base pair in DNA has been changed