Mutations Flashcards
Mutations
Changes in the genetic material of a cell which can alter phenotypes
Large scale mutations
Chromosomal changes
Small scale mutations
Nucleotide substitutions, insertions or deletions
Point mutations
Change a single nucleotide pair of a gene
-Substitution, silent, missense, nonsense
Substitution
Replacement of one nucleotide and its partner with another pair of nucleotides
Silent
Change still codes for the same amino acid
Missense
Change results in a different amino acid
Nonsense
Change results in a stop codon
Frameshift mutation
When the reading frame of the genetic information is altered
-Insertion and deletion of nucleotides, disastrous effects to resulting proteins
Large scale mutations
Nondisjunction, translocation, inversions, duplications, deletions
Nondisjunction
When chromosomes don’t separate properly in meiosis, results in incorrect number of chromosomes
Translocation
A segment of one chromosome moves to another
Inversions
A segment is reversed
Duplications
A segment is repeated
Deletions
A segment is lost
Natural selection and mutations
Anytime mutations occur they are subject to natural selection, genetic changes sometimes enhance the survival and reproduction of an organism
Prokaryotes can exchange genetic material through
Horizontal gene transfer
Transformation
Uptaking of DNA from a nearby cell
Conjunction
Cell to cell transfer of DNA
Transposition
Movement of DNA segments within and between DNA molecules
Biotechnology
Both DNA and RNA can be manipulated through genetic engineering
Gel electrophoresis defintion
Technique used to separate DNA fragments by size
Gel electrophoresis steps
- DNA loaded into wells at one end of a gel and an electric current is applied
- DNA fragments are negatively charged so they move toward the positive electrode
PCR, polymerase chain reaction
Method used in molecular biology to make several copies of a specific DNA segment
-Segments of DNA are amplified
-Results can be analyzed using gel electrophoresis
DNA sequencing
Process of determining the order of nucleotides in DNA
