Suppose the great, green galoofus lizard has 28 chromosomes in the nucleus of its unfertilized eggs. Predict how many chromosomes will be in the skin cells of a great, green galoofus lizard?

56

Explanation:

Because an unfertilized egg has half the chromosomes of a fertilized egg. The fertilized egg then splits, and continues splitting until the lizard is born. Always remember, whenever a question  talking about an unfertilized egg, it has half the chromosomes of a fertilized egg. One more side note, it doesn’t matter what body part you talk about. A skin cell will have the same number, and identical chromosomes compared to a heart cell. (So long as it’s the same organism, if it isn’t, but part of the same species, it will have the same number of chromosomes, but it may have a unique set of chromosomes). If you want me to go into detail, I can, just respond to this answer.

"do a testcross with a homozygous recessive plant."

several tissues working together form an organ, and several organs together make up an organisms.

the group of cell that carries out special jobs are tissue.