In corn plants, a dominant allele (I) inhibits kernel colour, but the recessive allele (i) permits colour when homozygous. At a different locus, the dominant gene P causes purple kernel colour, and the homozygous recessive genotype pp causes red kernels. If plants that are heterozygous at both loci are crossed, what will be the phenotypic ratio of the F1 generation?

Imagine you are given two tall plants, but you do not know their genotype (see Figure 16-12). There are three possibilities—they might both be TT or both Tt or one TT and the other Tt. Imagine you cross the two plants, wait for them to produce seeds, and then plant the seeds. If all resulting plants are tall, can you then determine what the genotypes of the two parents are? If approximately half the resulting plants are tall and about half are short, can you then figure out the genotypes of the parents?

You carry out a trihybrid cross (a cross in which the parental plants differ for three characters)  between a tall pea plant with round, yellow seeds (TT RR YY) and a short pea plant with wrinkled, green seeds (tt rr yy).  The parental plants are homozygous for all of the three characters. They are crossed to produce the F1 generation. Tall, round, and yellow are the dominant traits for each character. What will be the phenotypes of the F1 generation?

The diagram shows a plant that is heterozygous for two genes. G = yellow; g = green; R = round; r = wrinkled G Four different types of gametes are produced by a heterozygous individual when crossing over occurs, and two different types of gametes are produced when crossing over does not occur. What does this information reveal about crossng over? O Crossing over introduces variety by producing different combinations of alleles. O Crossing over reduces the incidence of DNA and chromosomal mutations. O Crossing over introduces variety in by creating types of genes. O Crossing over maintains the count of genes and the original alleles in both chromosomes. Copyright ©2021 Certica Solutions, Inc. https://encase.te21.com/Assessment/View/fc425cee-df10-4f28-a988-c3calbfa788a/675fd7db-03b1-48af-af8e-f6be62227cd7#