1:3
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.
No genes disappear in the F1 generation. Each of the F1 plants was heterozygous, having both dominant and recessive alleles. The recessive phenotype disappears in the F1 generation because all members of that generation carry a dominant allele. In the F2 generation, the recessive phenotype will reappear.
No genes disappear in the F1 generation. Each of the F1 plants was heterozygous, having both a dominant and recessive alleles. The recessive phenotype disappears in the F1 generation because all members of that generation carry a dominant allele. In the F2 generation, the recessive phenotype will reappear.
reappears in some plants in the F2 generation
3 dominant to 1 recessive
f2 generation
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.
In Mendel's experiments, particularly with the pea plants, the ratio of dominant to recessive phenotypes in the F2 generation was approximately 3:1. This means that for every three plants exhibiting the dominant trait, there was one plant exhibiting the recessive trait. Therefore, the correct answer to your question is not listed among the options provided.
By "test cross" you can know whether it homozygous dominant or heterozygous dominant...in homozygous both alleles code for the dominant trait, in heterozygous one allele is recessive (what you called a "hidden factor"). To perform the test cross, cross a homozygous recessive with the first generation. Lets suppose tall pea tree in the first generation is hetrozygous dominant (Xx) and has alleles X (dominant) and x (recessive). When we cross it with homozygous recessive (xx) X x x :Xx xx x :Xx xx we get half offspring showing dominant trait (Xx) and half showing recessive (xx). If the first generation was homozygous (which is not possible) the result would be X X x: Xx Xx x: Xx Xx all the offspring showing dominant trait and it doesn't really happen when we cross the first generation with homozygous recessive. It means that the genotype of first generation is heterozygous (has a hidden factor or a recessive allele x). Note:You must know what the recessive and dominant allele means...In presence of a dominant allele, recessice character is not expressed but it is present is heterozygous. If both alleles are recessive (homozygous recessive) then the recessive trait is expressed. If both the alleles are dominant (homozygous dominant) obviusly the dominant trait is showed by the individual.
To determine which alleles are recessive in the seed phenotype, you would need to compare the phenotype of the plants with known dominant phenotypes. Typically, if a phenotype appears in a generation that resembles the parents but differs from the dominant traits, those traits associated with the appearance of phenotype "a" are likely recessive. Observing the inheritance patterns in subsequent generations can further clarify which alleles are recessive based on the phenotypes that re-emerge when homozygous recessive individuals are bred.
Mendel's F1 generation plants showed only one of the two traits present in the parental generation. This indicated that the trait expressed in the F1 generation was dominant, while the other trait was recessive.
the tall trait was controlled by a dominant factor.