A triploid with 5 chromosomes in each set (3n = 15)is discovered.What is the probability of a meiosis in which all univalents pass to the same pole?

In the plant genus Triticum there are many different polyploid species,as well as diploid species.Crosses were made between three different species,and hybrids were obtained.The meiotic pairing was observed in each hybrid and is recorded in the following table.(A bivalent is two homologous chromosomes paired at meiosis,and a univalent is an unpaired chromosome at meiosis.) $\begin{array}{ll}\text { Species crossed to make hybrid } & \text { Pairing in hybrid } \\\text { 1. T. turdigum } \times \text { T. monococcum } & 7 \text { bivalents }+7 \text { univalents } \\\text { 2. T. aestivum } \times \text { T. monococcum } & 7 \text { bivalents }+14 \text { univalents } \\\text { 3. T. aestivum } \times \text { T. turdigum } & 14 \text { bivalents }+7 \text { univalents }\end{array}$

The first cross suggests a diploid and tetraploid individual were involved with one set of 7 chromosomes in common.Based on the other crosses,which species is the likely diploid individual?

In corn R is a gene for red aleurone;its recessive allele r determines colorless aleurone.A cross is made between a diploid r/r female and a trisomic R/r/r male.If pollen grains with extra chromosomes are inviable,the ratio of red to colorless kernels expected in the progeny would be: