Chapter 7 Flashcards
recessive trait
a trait that reappears in the second generation after disappearing in the first generation when parents with different traits are bred.
dominant trait
the trait observed in the first generation when parents that gave different traits are bred.
Gene
one set of instructions for an inherited trait.
allele
one of the alternative forms of a gene that governs a characteristic, such as hair color.
phenotype
an organism’s appearance or other detectable characteristic.
genotype
the entire genetic makeup of an organism; also the combination of genes for one or more specific traits.
probability
the likelihood that a possible future event will occur in any given instance of the event.
Punnett square
a diagram used to organize all the possible combination of genes for one or more specific traits.
homologous chromosome
chromosomes that have the same sequence of genes and the same structure.
meiosis
a process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in the production of sex cells.
sex chromosome
one of the pair of chromosomes that determine the sex of an individual.
pedigree
a diagram that shows the occurrence of a genetic trait in several generations of a family.
heredity
the passing of traits from parents to offspring.
