ch. 12 Flashcards
(23 cards)
Parental generation (P0)
first set of parents crossed in a genetic experiment (P0)
F1
first generation of offspring produced from cross-breeding
F2
second generation of offspring produced
reciprocal cross
\ two different strains of organisms are crossed twice, with the sexes of the parents switched in the second cross (determines if a trait is sex-linked)
dominant
a trait that appears more frequently than another
Recessive
a trait that is expressed only when genotype is homozygous
allele
one of two or more versions of a gene found at a specific location (locus) on a chromosome
phenotype
observable and measurable characteristics of an organism (height, eye color, hair color)
genotype
an organism’s genetic makeup (HH, Hh, hh)
homozygous
an individual possessing two identical alleles (hh, HH) of a gene for a specific trait
heterozygous
having two different versions of the same gene (Hh)
incomplete dominance
neither allele of a gene completely dominates the other
codominance
two alleles are expressed equally, and neither allele is dominant or recessive
wild-type
Any trait that naturally exists in over half of the wild population is considered wild type
variants
another version of something (chimps, apes, gorillas)
sex chromosomes
chromosomes that determine the sex of an individual
autosomes
any chromosome not considered a sex chromosome
X-linked
genes or traits located on the X chromosome
hemizygosity
having only one copy of a gene
carriers
organism or molecule that transports something else (like a gene)
lethal allele
mutant form of a gene that, when expressed in the phenotype, leads to the death of the organism
genetic linkage
genes located close together on the same chromosome to be inherited together during meiosis (blonde hair + blue eyes, brown hair + brown eyes)
