AP Biology Chapter 14 Quiz Flashcards
Referring to plants that produce offspring of the same variety when they self–pollinate
True–breeding
In genetics, the mating, or crossing, of two true–breeding varieties
Hybridization
The parent individuals from which offspring are derived in studies of inheritance; P stands for “parental”
P generation
The first filial, or hybrid, offspring in a series of genetic crosses
F1 generation
Offspring resulting from interbreeding of the hybrid F1 generation
F2 generation
Alternative versions of a gene that produce distinguishable phenotypic effects
Alleles
An allele that is fully expressed in the phenotype of a heterozygote
Dominant allele
An allele whose phenotypic effect is not observed in a heterozygote
Recessive allele
Mendel′s first law, stating that each allele in a pair separates into a different gamete during gamete formation
Law of segregation
A diagram used in the study of inheritance to show the results of random fertilization in genetic crosses
Punnett square
Having two identical alleles for a given gene
Homozygous
Having two different alleles for a given gene
Heterozygous
The physical and physiological traits of an organism, which are determined by its genetic makeup
Phenotype
The genetic makeup, or set of alleles, of an organism
Genotype
Breeding of an organism of unknown genotype with a homozygous recessive individual to determine the unknown genotype. The ratio of phenotypes in the offspring determines the unknown genotype
Testcross
An organism that is heterozygous with respect to a single gene of interest. All the offspring from a cross between parents homozygous for different alleles are monohybrids. For example, parents of genotypes AA and aa produce a monohybrid of genotype Aa
Monohybrid
An organism that is heterozygous with respect to two genes of interest. All the offspring from a cross between parents doubly homozygous for different alleles are dihybrids. For example, parents of genotypes AABB and aabb produce a dihybrid of genotype AaBb
Dihybrid
Mendel′s second law, stating that each pair of alleles segregates independently during gamete formation; applies when genes for two characters are located on different pairs of homologous chromosomes
Law of independent assortment
The situation in which the phenotypes of the heterozygote and dominant homozygote are indistinguishable
Complete dominance
The situation in which the phenotypes of both alleles are exhibited in the heterozygote
Codominance
The ability of a single gene to have multiple effects
Pleiotropy
A type of gene interaction in which one gene alters the phenotypic effects of another gene that is independently inherited
Epistasis
A heritable feature that varies continuously over a range rather than in an either–or fashion
Quantitative character
An additive effect of two or more gene loci on a single phenotypic character
Polygenic inheritance
The range of phenotypes produced by a single genotype, due to environmental influences
Norm of reaction
Referring to a phenotypic character that is influenced by multiple genes and environmental factors
Multifactorial
A diagram of a family tree showing the occurrence of heritable characters in parents and offspring over multiple generations
Pedigree
In genetics, an individual who is heterozygous at a given genetic locus, with one normal allele and one potentially harmful recessive allele. The heterozygote is phenotypically normal for the character determined by the gene but can pass on the harmful allele to offspring
Carrier
A technique of prenatal diagnosis in which amniotic fluid, obtained by aspiration from a needle inserted into the uterus, is analyzed to detect certain genetic and congenital defects in the fetus
Amniocentesis
A technique of prenatal diagnosis in which a small sample of the fetal portion of the placenta is removed and analyzed to detect certain genetic and congenital defects in the fetus
Chorionic villus sampling (CVS)
