Terms : Hide Images
| 298874649 | Chromosome theory of inheritance | a theory that says Mendelian genes have specific loci (positions) on chromosomes, and it is the chromosomes that undergo segregation and independent assortment | |
| 298874650 | Wild type | the normal phenotype for a character (the phenotype most common in natural populations) | |
| 298874651 | Linked genes | genes that are located on the same chromosome that tend to be inherited together in genetic crosses | |
| 298874652 | Genetic recombination | the production of offspring with combinations of traits differing from those found in either parent | |
| 298874653 | Parental types | offspring that are expected to inherit a phenotype that matches one of the parental phenotypes | |
| 298874654 | Recombinants | offspring with two nonparental phenotypes that have new combinations of seed shape or color (for example) | |
| 298874655 | Crossing over | occurs while replicated homologous chromosomes are paired during prophase of meiosis I, and is when one maternal and one paternal chromatid break at corresponding points and then are rejoined to each other | |
| 298874656 | Genetic map | an ordered list of the genetic loci along a particular chromosome | |
| 298874657 | Linkage map | a genetic map based on recombination frequencies | |
| 298874658 | Map units | the distance between genes (one of these is equal to a 1% recombination frequency) | |
| 298874659 | Cytogenetic maps | maps that locate genes with respect to chromosomal features, such as stained bands, that can be seen in the microscope | |
| 298874660 | Sex-linked gene | a gene located on either sex chromosome (although in humans the term has historically referred specifically to a gene on the X chromosome) | |
| 298874661 | Duchenne muscular dystrophy | a human sex-linked disorder that affects about one out of every 3,500 males born in the US | |
| 298874662 | Hemophilia | a sex-linked recessive disorder defined by absence of one or more of the proteins required for blood clotting | |
| 298874663 | Barr body | a compact object that the inactive X in each cell of a female condenses into -lies along the inside of the nuclear envelope | |
| 298874664 | Nondisjunction | an occasional mishap in which the member of a pair of homologous chromosomes do not move apart properly during meiosis I or sister chromatids fail to separate during meiosis II | |
| 298874665 | Aneuploidy | a condition when if either of the aberrant gametes unites with a normal one at fertilization, the offspring will have an abnormal number of a particular chromosome | |
| 298874666 | Trisomic | an aneuploid cell is said to be this for a certain chromosome if that chromosome is present in triplicate in the fertilized egg | |
| 298874667 | Monosomic | an aneuploid cell is said to be this for a specific chromosome if that chromosome is missing | |
| 298874668 | Polyploidy | the general term for chromosomal alteration when some organisms have more than two complete chromosome sets | |
| 298874669 | Deletion | occurs when a chromosomal fragment lacking a centromere is lost -the affected chromosome is then missing certain genes | |
| 298880194 | Duplication | a case (if meiosis is in progress) when a "deleted" fragment may become attached as an extra segment to a sister chromatid | |
| 298880195 | Inversion | produced when a chromosomal fragment may also reattach to the original chromosome but in reverse orientation | |
| 298880196 | Translocation | a rearrangement when a fourth possible result of chromosomal breakage is for the fragment to join a nonhomologous chromosome | |
| 298880197 | Down syndrome | an aneuploid condition that affects about one out of every 700 children born in the US -is usually the result of an extra chromosome 21 (three chromosome 21's) | |
| 298880198 | Genomic imprinting | a variation in phenotype depending on whether an allele is inherited from the male or female parent |
