Chapter 1
Complement of all genes for a given organism; the genetic material of a chromosome set
Genome
Dominant phenotype
the parental phenotype that is expressed in a heterozygote
Recombination
the process that generates a haploid product of meiosis whose genotype is different from either of the two haploid genotypes that constituted the meiotic diploid
Tetrad
(1) four homologous chromatids in a bundle in the first meiotic prophase and metaphase (note: alternative definition subsequent chapter)
Geneotype
What is the specific allele composition of a cell?
Mutation
a change in DNA sequence (as compared to wild type)
the probability that one or the other of two mutually exclusive events will occur is the sum of their individual probabilities
What is the sum rule?
an individual heterozygous at two genes (e.g. A/a.B/b)
Dihybrid
Diploid
a cell having two chromosome sets or an individual organism having two chromosome sets in each of its cells
Provide an example of a dihybrid cross.
A/a.B/b x A/a.B/b
a cross between two individuals identically heterozygous at two gene pairs
Outward manifestation of a specific genotype
substance of chromosomes; now known to include DNA and chromosomal proteins
What is Chromatin
Null hypothesis
a hypothesis that proposes no difference between two or more data sets
Recessive allele
An allele whose phenotypic effect is not expressed in a heterozygote
A cell/organism having identical alleles at a given gene(s) (e.g. A/A or a/a)
homozygous (= true-breeding)
Genetics
What is the experimental study of heredity/genes?
Molecular marker
site of DNA heterozgosity (difference), not necessarily associated with phenotypic variation, used as a tag for a particular chromosomal locus
unlinked or distantly linked segregating gene pairs assort independently at meiosis
Independent assortment (Mendel's 2nd Law)
Chi Square Test
What is aa statistical test used to determine the probability of obtaining observed proportions by chance, under a specific hypothesis?
Tester
an individual organism homozygous for one or more recessive alleles; used in a test cross
Allele
What is an alternate form of a gene (resulting from mutation)?
Reciprocal crosses
a pair of crosses of the type genotype A (female) x genotype B (male) and B (female) x A (male)
Parental gamete
any gamete with a genotype identical to one of the haploid parents that fused to form the diploid meiocyte
Second filial generation (F2)
The second generation resulting from a controlled cross between two known parents (P), generated by selfing/intercrossing the F1 generation
The Product Rule
The probability of two independent events occurring simultaneously is the product of their individual probabilities