Fill in the following blanks with suitable words :

(a) Genes always work in ......................

(b) In pea plants, the gene for dwarfness is………………………..whereas that for tallness is………………

(c) Most people have .................earlobes but some have ..............earlobes.

(d) A human gamete contains................... chromosomes whereas a normal body cell has ................... chromosomes in it.

(e) All races of man have.............blood groups.

(f) The.................chromosomes for a ...............are XX whereas that for a ......................are XY.