Because the possible combinations are DD, Dr, rD, and rr. When a dominant gene is present (D), then that gene is selected. The plants only have a one in four chance of getting a rr combo (r being recessive). It must inherit two recessive genes to display that trait.
Seeds to raise F1 generation
3.1
A dominant allele is an allele where its phenotype will always be represented when the allele for that gene is present. A recessive allele can be masked by a dominant allele when a dominant and recessive allele are present for the same gene. A recessive allele will only present itself when two recessive alleles for a trait are present.
Green is dominant, and albino is recessive. If you cross heterozygous plants, you will end up with about a 3:1 ratio of green to albino.
pea plants
F1 generation
F2 generation
F1 generation
F2 generation
3 dominant to 1 recessive
f2 generation
small heights and a dirty green color
When a first generation plant self pollinates, the ratio of dominant to recessive traits in the second generation plants is typically 3:1. This is based on Mendel's principle of segregation, which predicts that in a monohybrid cross, three plants will exhibit the dominant trait and one will exhibit the recessive trait.
f2 generation
Unless the alleles are codominate (which Mendel did not have in pea plants), one will be dominate and will be what you see (phenotype) and one will be recessive and you will not see it.
In a monohybrid cross of tall dominant and dwarf recessive plants, all the F1 plants will be tall. This is because the tall trait is dominant over the dwarf trait, so the presence of one dominant allele is sufficient to exhibit the tall phenotype. The dwarf trait will be masked in the F1 generation.
they were all hybrids