In genetics, the use of chequer board was done by

When an individual is having both the alleles of a contrasting character, it is said to be

Definitions / Explanation : Test cross
 

In Mendel's experiment nature of seed coat, flower colour, position of flower, pod colour, stem height etc. are reffered to as

Test cross in plants or in Drosophila involves crossing

Mendel's principle of segregation means that the germ cells always receive