The experiment shown in the given figure has been carried out by Morgan to show the phenomenon of linkage and recombination. If in cross $I$, genes are tightly linked and in cross $II$, genes are loosely linked then what will be the percentage of recombinants produced in cross $I$ and cross $II$ respectively?

For the preparation of genetic maps, the recombination frequencies between genes are additive over short distances but not over long distances due to

Frequency of crossing over in a chromosome is an index of

In Drosophila, long wing and broad abdomen characters are dominant over to characters vestigeal wing and narrow abdomen. A pure breeding Drosophila having long wings and broad abdomen is crossed with a pure breeding vestigeal-winged and narrow-abdomened Drosophila. Two of the $F_1$ individuals were crossed and the following results were produced in the $F_2$ generation Long wing, broad abdomen in $482$ Drosophila. Vestigeal wing, narrow abdomen in $154$ Drosophila. Which one of the following is illustrated by these results

Mendel observed that some characters did not assort independently. Later researchers found it to be due to