Term
| Chromosome Theory of Inheritance |
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Definition
| A basic principle in biology stating that genes are located on chromosomes and that the behavior of chromosomes during meiosis accounts for inheritance patterns. |
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| An individual with the phenotype most commonly observed in natural populations; also refers to the phenotype itself. |
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| A gene located on a sex chromosome (usually the X chromosome), resulting in a distinctive pattern of inheritance. |
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| Duchenne Muscular Dystrophy |
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Definition
| A human genetic disease caused by a sex-linked recessive allele; characterized by progressive weakening and loss of muscle tissue. |
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| A human genetic disease caused by a sex-linked recessive allele resulting in the absence of one or more blood-clotting proteins; characterized by excessive bleeding following injury. |
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| A dense object lying along the inside of the nuclear envelope in cells of female mammals, representing a highly condensed inactivated X chromosome. |
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| Genes located close enough together on a chromosome that they tend to be inherited together. |
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| General term for the production of offspring with combinations of traits that differ from those found in either parent. |
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| An offspring with a phenotype that matches one of the parental phenotypes; also refers to the phenotype itself. |
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| An offspring whose phenotype differs from that of the parents; also refers to the phenotype itself. |
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| The reciprocal exchange of genetic material between nonsister chromatids during prophase I of meiosis. |
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| An ordered list of genetic loci (genes or other genetic markers) along a chromosome. |
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| A genetic map based on the frequencies of recombination between markers during crossing over of homologous chromosomes. |
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| A unit of measurement of the distance between genes. One map unit is equivalent to a 1% recombination frequency. |
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| A chart of a chromosome that locates genes with respect to chromosomal features distinguishable in a microscope. |
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Definition
| An error in meiosis or mitosis in which members of a pair of homologous chromosomes or a pair of sister chromatids fail to separate properly from each other. |
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| A chromosomal aberration in which one or more chromosomes are present in extra copies or are deficient in number. |
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| Referring to a cell that has only one copy of a particular chromosome instead of the normal two. |
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| Referring to a diploid cell that has three copies of a particular chromosome instead of the normal two. |
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| A chromosomal alteration in which the organism possesses more than two complete chromosome sets. It is the result of an accident of cell division. |
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| 1) A deficiency in a chromosome resulting from the loss of a fragment through breakage. 2) A mutational loss of one or more nucleotide pairs from a gene. |
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Definition
| An aberration in chromosome structure due to fusion with a fragment from a homologous chromosome, such that a portion of a chromosomal is duplicated. |
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| An aberration in chromosome structure resulting from reattachment of a chromosomal fragment in a reverse orientation to the chromosome from which it is originated. |
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| An aberration in chromosome structure resulting from attachment of a chromosomal fragment to a nonhomologous chromosome. |
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| A human genetic disease caused by the presence of an extra chromosome 21; characterized by mental retardation and heart and respiratory defects. |
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Definition
| A phenomenon in which expression of an allele in offspring depends on whether the allele is inherited from the male or female parent. |
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