Chapter 17: Mutations Flashcards
What is a mutation?
A spontaneous change in the sequence of nucleotides in a gene (changes order of ATCG)
What are the two types of mutations in nucleotides
Point mutations and framshift
What happens in point mutations?
A single nitrogen-containing base changes
What are the three types of point mutations
Silent mutation (no amino acid change)
Missense (change in amino acid)
Nonsense (change to stop codon)
What happens in frameshift mutations?
A shift in the sequences of subsequent nitrogen-bases occur
What are the two types of frameshift mutations?
Insertions (adding base(s))
Deletions (removing bases(s))
How would a mutation involving adding and removing of bases not be a framshift?
If entire codon(s) is / are removed
Which mutation is more serious?
Frameshift mutation
What are chromosomal mutations?
When chromosomes fail to seperate properly, resulting in extra or fewer chromosomes
What is down syndrome caused by?
Nondisjunction, which is the failure of a pair of chromosomes to seperate during sperm or egg formation
What are some causes of mutations?
Spontaneous / Random mutations or Mutagens (environmental factors like radiation)
