Unit 6 - topic 7 Flashcards
mutations
- changes in the genetic material of a cell, which can alter phenotypes
- primary source of genetic variation
- normal function and production of cellular products is essential
new phenotypes can be cause by
disruption
changes can be
large or small scale
large scale
chromosomal changes
small scale
nucleotide substitutions, insertions, or deletions
point mutations
change a single nucleotide pair of a gene
substitution
replacement of one nucleotide and its partner with another pair of nucleotides
silent
change still codes for the same amino acid (remember: redundancy in the genetic code)
missense
change results in a different amino acid
nonsense
change results in a stop codon
frameshift mutation
when reading frame of the genetic information is altered
disastrous effects to resulting proteins
insertion
nucleotide is inserted
deletion
nucleotide is removed
large scale mutations
affect chromosomes
nondisjunction
when chromosomes do not separate properly in meiosis
results in the incorrect number of chromosomes
translocation
segment of one chromosome moves to another
inversion
segment is reversed
duplication
segment is repeated
deletion
segment is lost
Any time mutations occur, they are subject to
natural selection
genetic changes can sometimes enhance the survival and reproduction of an organism
horizontal gene transfer
what prokaryotes can exchange genetic material through
if there is a mutation that is beneficial to the survival and reproduction of that prokaryote then it can also be transferred
transformation
uptaking of DNA from a nearby cell
transduction
viral transmission of genetic material
conjugation
cell to cell transfer of DNA
transposition
movement of DNA segments within and between DNA molecules
