Genetically Speaking
allele
One of the alternative forms of any gene on a chromosome. Each allele
represents a different variation of a physical trait, and each has one
corresponding allele on the chromosome's paired counterpart. For example, one
blue-eye allele will have one corresponding allele that arrives either a
blue-, green- or brown eye trait.
chromosome
Structure in the nucleus of a cell that carries genes. Each species has a
constant number of chromosomes set in pairs in each body cell; the horse has
64, or 32 pairs.
Dominant
Pertaining to a gene that guarantees the appearance of its trait in the
offspring, regardless of the nature of the gene with which it is paired.
DNA (deoxyribonucleic acid)
protein chains in cell nuclei that determine individual hereditary
characteristics.
gene
Unit of hereditary material in the nucleus of a cell; carries the protein
code for the development of a specific trait or characteristic in offspring
cells.
recessive
genetic trait that appears only when both of its corresponding alleles are
identical and in the absence of its dominant counterpart allele. For example,
the recessive trait of blue eyes will only appear in persons only if both
parents pass on blue-eye genes. Otherwise, a dominant brown-eye gene will
subordinate the blue eye and the offspring will be brown -eyed.
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