Vocabulary
An allele whose effect is masked in a heterozygote
What is recessive
Cross: Tt × tt → genotype ratio
What is 1 Tt : 1 tt
Number of gamete types produced by AaBb
Red flower × white flower → pink offspring
What is incomplete dominance
Probability of recessive phenotype from Tt × Tt
What is 1/4
Cross used to determine an unknown genotype
What is test cross
You observe a dominant phenotype. What are the possible genotypes?
What is TT or Tt
Cross: AaBb × AaBb → phenotype ratio
What is 9:3:3:1
AB blood type example represents what inheritance?
What is codominance
Probability of two recessive traits from AaBb × AaBb
What is 1/16
When one gene affects multiple traits
What is Pleiotropy
A test cross yields a 1:1 ratio. What is the unknown genotype?
What is heterozygous
If genes are linked, what happens to expected ratios?
What is they deviate from Mendelian ratios
In incomplete dominance, what is the phenotype ratio of a heterozygous cross?
What is 1:2:1
Probability of at least one dominant allele in Tt × Tt
What is 3/4
When one trait is controlled by multiple genes
What is polygenic inheritance
If two heterozygotes are crossed, what % of offspring are homozygous recessive?
What is 25%
Cross: AaBb × aabb → genotype ratio
What is 1:1:1:1
Why does incomplete dominance NOT show a 3:1 ratio?
What is because heterozygotes have a distinct phenotype
If first child is recessive, does it affect second child’s probability?
What is no
When alleles are expressed equally in a heterozygote
What is codominance
If 100 offspring are produced from Tt × Tt, how many are expected to be heterozygous?
What is 50
How many total genotypes are possible in a dihybrid cross?
What is 9
If RR = red, WW = white, what is genotype of pink?
What is RW
Probability BOTH traits show dominant phenotype in dihybrid cross
What is 9/16