I think a punnett square is the easiest way to illustrate inheritance and make it understandable.

Each single morph het animal has 1 mutant gene and one normal gene. Each single morph homozygous animal has 2 mutant genes. Put the sire's genes along the top, and the dam's along the side--so you will have (for example) "Albino" and 'Normal" along the top, for a het male. If you have a homozygous female (an albino), put "Albino", and "Albino" along the side. Then you just fill in the rest of the square--each offspring will have one gene from the mother, and one from the father.

http://en.wikipedia.org/wiki/Punnett_square

http://www.newenglandreptile.com/gen...recessive.html

You can use a punnett square to figure out the percentages for any combination you choose to cross.

66% het of course means there's a 2/3 chance the animal will be het (and a 1/3 chance it is a normal).