Search results
Results from the WOW.Com Content Network
Monohybrid, also called “single gene test cross”, is used to observe how homozygous offspring express heterozygous genotypes inherited from their parents. The implantation of monohybrid crossing includes signifying the alleles by using characters – recessive allele often is indicated with a lower-case letter, and the dominant allele is ...
A monohybrid cross is a cross between two organisms with different variations at one genetic locus of interest. [ 1 ] [ 2 ] The character(s) being studied in a monohybrid cross are governed by two or multiple variations for a single location of a gene.
The forked-line method (also known as the tree method and the branching system) can also solve dihybrid and multi-hybrid crosses. A problem is converted to a series of monohybrid crosses, and the results are combined in a tree. However, a tree produces the same result as a Punnett square in less time and with more clarity.
Later work by corn breeders produced inbred lines with sufficient vigor for practical production of a commercial hybrid in a single step, the single-cross hybrids. Single-cross hybrids are made from just two original parent inbreds. They are generally more vigorous and also more uniform than the earlier double-cross hybrids.
Complementation tests can also be carried out with haploid eukaryotes such as fungi, with bacteria, and with viruses such as bacteriophage. [1] Research on the fungus Neurospora crassa led to the development of the one-gene-one-enzyme concept that provided the foundation for the subsequent development of molecular genetics.
To select the most promising parents for hybrid production, test crosses conducted in various environments are required, because the variance of their specific combining ability under differing environmental conditions is the most important component in evaluating their potential as parents to produce promising hybrids.
In his cross-pollination experiments involving two true-breeding, or homozygous, parents, Mendel found that the resulting F1 generation was heterozygous and consistent. The offspring showed a combination of the phenotypes from each parent that were genetically dominant. Mendel's discoveries involving the F1 and F2 generations laid the ...
Crossing over and DNA repair are very similar processes, which utilize many of the same protein complexes. [10] [11] In her report, "The Significance of Responses of the Genome to Challenge", McClintock studied corn to show how corn's genome would change itself to overcome threats to its survival. She used 450 self-pollinated plants that ...