Chapter 9: Mendelian Genetics And Mutation Flashcards
theory of blending inheritance
proposed that traits present on the parents mixed together like paint to produce a new combination in the offspring
horticulture
the artificial selection of plants
hybridizing
the process of crossing two different types of plants
true breeding
strains of plants that contain only one form of a trait
reciprocal cross
an experimental cross in which 2 different forms of a trait are interchanged between male and female plants
monohybrid cross
an experiment that uses parent varieties (or strains) differing in a single trait
self-crossing/self-fertilization
a plant is pollinated with its own pollen as opposed to pollen from another plant
genes
heritable factors; discrete unit of hereditary information
alleles
alternate forms of a gene
homozygous
has two identical alleles for a given trait
heterozygous/hybrid
has two different alleles for a given trait
genotype
an allelic combination
phenotypes
the physical expression of genes
recombination
the occurrence of an offspring whose phenotype differs from that of the parent
test-cross
crossing an organism of an unknown genotype with a homozygous recessive individual to determine the unknown genotype; the ratio of phenotypes in the offspring determines the unknown genotype
inheritance
the way traits are passed on from generation to generation
back cross
a test cross with the homozygous recessive parent (a reverse test cross)
Punnett square
invented by Reginald Punnett in 1905. It is a grid that shows all the possible gametes formed by each of the parents and all of the possible genotypes and phenotypes in the offspring.
dihybrid
a breeding experiment that uses parental varieties differing in two traits
independent assortment
the alleles for the two different traits must assort independently with respect to one another
meiosis
a type of cell division in sexually reproducing organisms which results in gametes with half of the chromosome number of the original cell
recombination
a process in meiosis that results from homologous chromosomes segregating into different gametes, resulting in multiple possible allele combinations
the multiplicative law of probability
the probability of two independent events co-occurring is the product of their individual probabilities
trihybrid
a breeding experiment that uses parental varieties differing in three traits
sickle cell anemia
caused by a defective hemoglobin protein in red blood cells which causes the cells to deform to a sickle shape and triggers blood clotting and other symptoms
the additive rule
the probability of one or another of two mutually exclusive (or separate) events occurring equals the sum of their individual probabilities
intermediate inheritance
the heterozygote genotype has a unique phenotype which is intermediate to the two parental phenotypes; neither allele dominates