Mendel-genetics Flashcards
What were Mendel’s conclusions based on his experiment?
traits are inherited as discrete units, organisms inherit one copy of a gene from each parent, and law of segregation,
homozygous
alleles are identical to each other
heterozygous
alleles are different from each other
genotype
the makeup of a specific gene ( heterozygous or homozygous plus dominant or recessive)
phenotype
the physical expression of a trait
Alleles
forms of a trait that have a different sequence of nucleotides at the locus
Law of segregation
a gamete gets only one form of an allele. This occurs in anaphase 2 where the chromatids separate
What to do if you don’t know the genotype?
Use a Punnett square and crossbreed with a homozygous recessive gene.
Law of independent assortment
increase variation because crossing over occurs frequently
incomplete dominance
shows a blended phenotype ex; red flower w/ white flower makes a pink flower
co-dominance
2 alleles can affect the phenotype equally or separately. ex; blood ( A, B, O )
pleiotrophy
the ability for a gene to affect organisms in several ways ex dwarfism
epistasis
one gene masks another gene
X chromosome
if a sex-linked trait is recessive the female will only inherit it if she has two mutated genes but if there’s only one she is the carrier
Autosomal disease
in a pedigree, if the male and female are 50/50 with the disorder.
