Chap 12 Inheritance patterns Flashcards
Meiosis separates homologous pairs of
chromosomes so that a gamete receives
only one.
Law of Segregation
Which homologue a zygote (offspring)
receives is random based on the
alignment of tetrads
Law of Independent Assortment
Which homologue a zygote (offspring)
receives is random based on the
alignment of tetrads DURING
Metaphase I
Meiosis separates homologous pairs of
chromosomes so that a gamete receives
only one DURING
Anaphase I
alternative versions of genes
Alleles
account for variations of inherited traits
Alleles
heterozygous for both characters
dihybrids
Two dominant alleles affect the phenotype in
separate, distinguishable way
Codominance
The phenotype of F1 hybrids is somewhere between the phenotypes
of the two parental varietie
Incomplete dominance
gene has multiple phenotypic
effects
pleiotropy
Seemingly unrelated character traits controlled by one
gene
pleiotropy
gene at one locus alters the
phenotypic expression of a gene at a second locus
epistasis
An additive effect
of two or more genes
on a single phenotype
polygenic
inheritance
Recessively inherited disorders show up only in
individuals
homozygous
heterozygous individuals who
carry the recessive allele but are phenotypically
normal
Carriers
Thick mucus builds up in some internal organs
Cystic Fibrosis
Abnormal absorption of nutrients, chronic bronchitis,
infections
Cystic Fibrosis
Cystic Fibrosis is
Pleiotropic
Insufficient oxygen exchange to tissues
Sickle-cell disease
Sickle-cell disease is
Incomplete and Codominance
more likely to produce homozygous recessive genotypes.
consanguineous
liquid that bathes the fetus is removed
and tested
amniocentesis