What is the name of the pea species used by Bateson and Punnett in their experiments?

In a somatic cell,if the arrangement of genes is such that dominant alleles are present on one chromosome and recessive alleles are present on the other chromosome of a homologous pair,what is this arrangement called?

The evidence that crossing over occurs at the four-stranded stage and not at the two-stranded stage of the chromosomes comes from:

How many types of gametes will be produced by a male Drosophila having the following arrangement of two genes ($y$ and $w$) on the $X$-chromosome?

Which event during cell division is responsible for the emergence of new characteristics in the next generation of organisms?

Describe linkage and recombination in detail.