monohybrid cross - a cross-breeding, which is characterized by a distinct parental forms from each other by a pair of available alternative, contrasting characters.The sign refers to any feature of the body, any of its property or quality by which is possible to distinguish individuals.In plants, this property is, for example, the shape of the corolla (asymmetric or symmetric), its color (white or purple), etc. D. The signs also include the rate of maturation (late ripening or ripening), and the resistance or susceptibility to certain diseases.
All properties together, since the outer and ending certain features in the structure or functioning of cells, organs, tissues, called phenotype.This concept may be used with respect to one of the available alternative features.
manifestation of the properties and signs carried out under the supervision of existing hereditary factors - in other words, genes.Collectively genes are genotype.
monohybrid cross Mendelian crossbreeding pea presented.At the same time there are such well enough visible alternative properties as white and purple flowers, green and yellow color of immature beans, wrinkled and smooth seeds and others.
Spending monohybrid cross, Mendel, Austrian botanist × I X., Found that the first generation (F1) hybrid plants all had flowers purple hue, white coloration is not apparent.Thus was launched the first law of Mendel's patterns of uniformity of the first generation.In addition, scientists have found that the first generation of all of the samples were homogeneous and the seven studied their characteristics.
Thus monohybrid cross implies for individuals of the first generation of the availability of alternative signs only one parent while the other parent characteristics seem to disappear.Prevalence of properties Mendel called domination, and the signs themselves - dominant.Do not manifested as a scientist called recessive.
Spending monohybrid cross, Mendel subjected to self-pollination of the first generation hybrids are grown.Formed in which sowed the seeds of a scientist again.As a result, he received the following, the second generation (F2) hybrids.The obtained samples mentioned cleavage by alternative features in the approximate ratio of 3: 1.In other words, three-quarters of individuals of the second generation have a dominant properties, and one-quarter - recessive.As a result of these experiments, Mendel concluded that the recessive trait in the samples was suppressed, but has not disappeared, manifesting itself in the second generation.This compilation has been called "the Law of splitting" (the second law of Mendel).
further monohybrid cross scientist conducted in order to identify how the inheritance will occur in the third, fourth and subsequent generations.He grew patterns using self-pollination.The experiments revealed that the plants, the symptoms of which are recessive (white flowers, for example), is performed in subsequent generations of offspring reproduction only with those (recessive) properties.
somewhat differently behaved plants of the second generation, the properties of which have been named Mendel dominant (owners, for example, purple flowers).Among these samples, scientists analyzing progeny revealed two groups having the absolute differences in appearance for each specific feature.
for individuals differ in two ways, used dihybrid cross.The task of determining genotypes and phenotypes are relatively simple, at their decision applied Mendel's laws.
