A monohybrid cross is a cross between two individuals with different alleles at one genetic locus. If we cross two heterozygous individuals (Aa), then the percentage of offsprings with recessive phenotype will be: Aa x Aa = AA Aa Aa aa, so recessive phenotypes would be 1/4 = 25%.
Can two heterozygous individuals produce offspring which show the recessive trait?
Unaffected parents can produce affected offspring if both parents are carriers (heterozygous) for the trait being tracked in the pedigree. Recessive traits are typically not expressed in every generation. Lastly, males and females are equally likely to express a recessively inherited trait.
What is the phenotype of the heterozygotes offspring?
Mendel observed that a heterozygote offspring can show the same phenotype as the parent homozygote, so he concluded that there were some traits that dominated over other inherited traits. However, the relationship of genotype to phenotype is rarely as simple as the dominant and recessive patterns described by Mendel.
What does a 3 1 ratio mean in genetics?
The F2 generation always produced a 3:1 ratio where the dominant trait is present three times as often as the recessive trait. Mendel coined two terms to describe the relationship of the two phenotypes based on the F1 and F2 phenotypes.
Is AA heterozygous or homozygous?
Two dominant alleles (AA) or two recessive alleles (aa) are homozygous. One dominant allele and one recessive allele (Aa) is heterozygous.
Which allele is always written first?
The alleles are represented by letters. The letter chosen is usually the first letter of the trait.