Mutations Or Something Flashcards
Germ cell mutation
Occurs in the gametes. They don’t affect the organism, but are passed to the offspring. Provide the variation on which natural selection acts
Somatic cell mutation
Occurs in the body cells. Passed to daughter cells by mitosis
Deletion
A piece of chromosome is deleted
Duplication
An extra copy of a portion of a chromosome is produced
Inversion
A section of chromosome breaks off and reattaches in the opposite direction
Translocation
A section breaks off from one chromosome and attaches to another
Nondisjunction
When chromosome pairs fail to separate during meiosis
Monosomy
When a zygote has only one chromosome of a particular pair
Trisomy
When a zygote has three of a particular chromosome
Point mutation
The substitution, addition, or deletion of a single nitrogen base from a codon
Frame shift mutations
Point mutation in which a nitrogen base is added or deleted
Mutagens
Environmental factors that damage DNA
Polyploidy
When an organism has an extra set of chromosomes in its cells
Genome
The full set of genetic info that an organism carries in its DNA
Karyotype
A photograph is taken of chromosomes during mitosis. The complete diploid set of chromosomes are cut out and grouped in pairs from largest to smallest
Sex chromosomes
Chromosomes that determine an individual’s sex
Autosomes
All the chromosomes that are not sex chromosomes
Sex linked gene
Gene found on the x or Y chromosome
Sex linked trait
A trait determined by genes found on the x or Y chromosome
Linkage group
All of the genes located on one chromosome
Chromosome map
Diagram of alleles position on a chromosome
Map unit
Distance between alleles on a chromosome. Measured by how often the two alleles are separated during crossover
Crossing over
Homologous chromosomes exchange genetic material during meiosis
Pedigree
A chart that shows how a trait is inherited over several generations in a family
Carrier
Someone who is heterozygous for a recessive trait. They don’t show the trait but they can pass it to their offspring
Sex linked trait
Genes for these traits are found mostly on the X chromosome
Mutation
Change in DNA that may result in a new phenotype
