Question

pls explain how to make a dihybrid cross

Answer 1

take any two traits of the plant/ any species you want, now lets say the example given in book is of yellow or green and wrinkled or round seeds in pea plant. so, lets take YY for yellow and yy for green, similarly WW for wrinkled and ww for round.

now, lets take male having YYWW and female having yyww here, YYWW is dominant. therefore,

in parents-   YYWW  X  yyww

so, genotype will be  YW and YW      yw and yw

making bonnet square,

                         male       YW             YW

                         female

                         yw         YyWw      YyWw

                         yw         YyWw       YyWw

 all the f1 progenies will be heterozygous

now  for f2 progenies,

  parents-  YyWw    X     YyWw

genotype will be male- YW yw Yw and yW     female- YW yw Yw and yW

so in the square we get,  m-      YW           yw          Yw        yW

                             f-       YW     YYWW   YyWw     YYWw   YyWW

                             f-       yw      YyWw     yyww       Yyww     yyWw

                             f-       Yw     YYWw    Yyww       YYww     YyWw

                             f-       yW     YyWw    yyWw        YyWw    yyWW

giving us ratio of 9:3:3:1                                                       <m- male, f-female>

hope it helped.. :) mark brainliest if you think it helped