Bio-Pac 06: Vocabulary Flashcards
Genotype
The gene combination.
Phenotype
The way an organism looks and behaves. (Two organisms can look alike (phenotype), but have different gene combinations (genotype )
Allele
Mendel concluded that each organism has two factors for each of its traits. These factors are genes and are located on the chromosomes. Genes exist in alternative forms. We call these different gene forms alleles .
Probability
The likelihood that each will occur .
Heterozygous
An organism is heterozygous for a trait if its two alleles for the trait are different .
Homozygous
An organism is homozygous for a trait if its two alleles for the trait are the same .
First Generation
The first generation of offspring. If both parents are homozygous for different genes/alleles then the first generation will have different genes, genotypes, and phenotypes than their parents. It was as if the recessive allele never existed .
Second Generation
The second generation of offspring. If both parents are heterozygous then the second generation will have the gene that disappeared in the first generation reappear one-fourth of the time in the second generation .
Hybrid
Heterozygous for a gene pair
Autosome
The 22 two pairs of matching homologous chromosomes that are NOT involved in sex determination.
Sex Chromosome
The two chromosomes that determine the sex of an individual.
Carrier
A carrier is a heterozygous individual appears the same phenotypically as onethat is homozygous dominant.
Nondisjunction
The failure of homologous chromosomes to separate properly during meiosis.
Purebred
Bred from parents that are homozygous for ALL their gene pairs.
Karyotype
Chart of homologous chromosomes pair.
