Generating Diversity II Flashcards
What is a deletion?
broken segment is lost from the chromosome and can cause severe problems
What is duplication?
segment is broken from one chromosome, inserted into homologous and adds to alleles already there, can be harmful or beneficial, can occur from uneven crossing over
What is an inversion?
a broken segment reattaches, but in the opposite direction, can be either harmful or beneficial, genes are either broken (lose function) or transferred to a new location
What is translocation?
broken segment attached to a non-homologus chromosome, usually reciprocal (2 non-homologous chromosomes exchange segments)
What is non-disjunction?
failure of chromosomes to separate in first meiotic division
What is aneuploidy?
missing or extra chromosomes, can also occur in sex chromosomes
What is polyploidy?
one or more extra copies of chromosomes, occurs because failure of spindle to function normally, very lethal in animals
What is an euploid?
normal set of chromosomes
What is gene duplication?
any process that produces 2 identical copies of a gene
What are the 3 methods of gene duplication?
- Whole genome duplication
- Unequal crossing over
- Replication of transposable elements
What is whole genre duplication?
when cells have the wrong number of chromosomes
What is unequal crossing over?
chromosomes cross at different places
What is replication of transposable elements?
makes genes that are functionally redundant, one is usually lost, if both remain they usually evolve differently
What is exon shuffling?
creates new genes by combining parts of 2 or more genes and the gene encodes for a protein with an unprecedented function
What are the 3 steps to create retroviruses?
- copies of single stranded RNA inserted into double stranded DNA
- Viral DNA inserted into host
- Host passes inserted viral DNA (provirus)
