If you wanted to get technical, I don't think any of us know offhand how many genes a snake has--but the number is probably over 30,000.
Baby snakes are created from 2 sets of genes. One set comes from the mother, and the other from the father. Reproductive cells (eggs and sperm) have only half the number of genes needed to make an animal. One set of chromosomes. Each cell of your body contains 2 complete sets of chromosomes.
When we talk about which genes our snakes have, we're actually talking about mutations in single genes. A heterozygous animal has one mutant gene that keys for one very specific thing (from one parent), and one normal gene (from the other parent). A homozygous animal has 2 mutant genes that key for one very specific thing (both parents contributed the same mutant gene).
What the animal actually looks like has to do with whether or not the genes are 'expressed'--in other words, whether the snake's body is affected by the mutant gene. Co-dominant mutant genes are expressed when only one copy is present. Recessive genes are not expressed when only one copy is present. This is because the normal gene is a dominant gene, so it is expressed instead of the mutant gene in animals that are het for a recessive trait.
Now, if your question were, 'how many total mutant genes does a killerbee have?', the answer would be '3'. If the question is 'how many different mutant genes does a killerbee have?', then the answer is '2'.
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