| A | B |
|---|
| alelles | different forms of the same gene |
| dominant allele | the allele that determines the trait whenever it is present |
| recessive allele | the allele that determines the trait only when the dominant allele is not present |
| genotype | the genetic composition of the organism |
| homozygous | both alleles for a gene are the same (either both dominant or both recessive) |
| heterozygous | one allele is dominant and one allele is recessive |
| phenotype | the physical traits determined by the genes |
| mutagen | an agent that causes a genetic mutation |
| monohybrid cross | the result of male and female mating with regard to a single trait |
| dihybrid cross | the result of male and female mating with regard to two traits |
| autosome | a chromosome that does not determine the sex of the individual |
| pedigree | the record of ancestors for an individual (or family) showing parent/offspring relationships across generations, also called a family tree |
| Law of Independent Assortment | each allele for a trait moves into the gametes without influencing the other alleles for other traits |
| sex chromosomes | two chromosomes that determine the sex of an individual |
| Law of Segregation | during gametogenesis, each gamete receives only one allele for every gene |
| codominance | a type of inheritance where neither allele is dominant over the other |
| polygenic inheritance | traits that are the result of multiple genes working together such as height and skin color |
| adaptive developmental plasticity | the ability to change phenotype depending on environmental conditions |
| Human Genome Project | the completed gene sequencing of all 46 human chromosomes |
| nondisjunction | a chromosomal abnormality in resulting from spindle fiber failure |
| spontaneous mutation | the type of mutation that occurs during the DNA replication process that is usually fixed |
| translocation mutation | the type of mutation that involves the movement of a sequence of nucleotides from one location to another either on the same chromosome or to another chromosome |
| duplication mutation | a mutation involving making a copy of a segment of DNA and placing the copy somewhere else on the same chromosome or another |
| inversion mutation | a mutation in which a segment leaves its original site and inserts in another site in the inverse order |
| conjugation | moving a segment of DNA from one bacterium to another through use of tube-like structure |
| transformation | a live bacterium absorbing a section of DNA released into the local environment by a dead bacterium |
| transduction | the transfer of DNA from one bacterium to another via a virus |
| point mutation | a mutation in which one nucleotide is incorrectly copied during replication. A type of substitution mutations |
| silent mutation | a type of point mutation that does not affect on a protein |
| nonsense mutation | a type of point mutation that causes the production of a completely different protein that is too short and doesn't function as it should |
| missense mutation | a type of point mutation that causes the wrong protein to be made that might do the job or at least partially do the job |
| reading frameshift | a type of mutation in which a nucleotide is either deleted or added |
| somatic cells | the cells involved in everyday activities of the organism |
| germ cells | the cells responsible for producing gametes |
| linkage | the term used to describe genes close together on the same chromosome that always stay together during crossing-over in prophase I |
| XX genes | the sex genes that indicate a human female |
| XY genes | the sex genes that indicate a human male |
| sex-linked genes | genes that are located on the X and Y genes in humans |
| chromosomes 1 - 22 | in humans the chromosomes that are not a sex chromosomes |
| chromosome 23 | in humans the chromosome that indicate the sex of the individual |
