MORE GENETICS PROBLEMSDragons either have forked tongues or they do not. It is a trait determined bya pair of genes in each dragon (use F and f as genes). If dragons with forked tongues mate the offspring always have forked tongues. If a dragon without a forked tongue that was homozygous for the trait mated with a forked tongue dragon what would be the phenotypic ratio of their offspring?

What would be the genotypic ratios if one of the previous dragon offspring matedwith this one?

If the dragon above had offspring with forked tongues could both of the above dragon’s parents NOT have forked tongues? Could its mate NOT have a forkedtongue?

Diagram the genotypic relations among the dragon generations from theprevious slide.

Suppose you run a dragon ranch in Rhode Island (Houston metro is bigger thanthe entire state!) with plenty of dragons having both kinds of tongue. How could you determine whether or not your prize male dragon without a forked tongue isheterozygous?

Some dragons have horns as a dominant trait (use H for the dominant gene)and others are hornless (use h for the recessive gene).

HORNLESS HORNED

If a hornless dragon WITHOUT a forked tongue mates with a horned forked-tongue dragon and they can produce ONLY some offspring that are hornedwith forked tongues and some that are hornless WITHOUT forked tongueswhat are the genotypes of the parents?

DIHYBRID GENETICS PROBLEMS

What would be the genotypic and phenotypic ratios for a cross between the twokinds of offspring from the preceding slide?

If a horned dragon without a forked tongue that had a parent with a forked tongue andanother parent without horns mates with a horned forked-tongue dragon and they have ahornless offspring without a forked tongue what are the most probable genotypes of all the dragons mentioned here?

Red-eyed dragons always produce offspring with red eyes and white-eyed dragonsalways produce offspring with white eyes BUT a red-eyed dragon and a white-eyed dragon will always produce offspring with pink eyes. What would be the genotypicand phenotypic ratios for the offspring of a red-eyed dragon and a pink-eyed dragon?

If a pink-eyed hornless dragon mates with a red-eyed horned dragon that had ahornless parent what would the genotypic and phenotypic ratios of their possibleoffspring be?

Dragons have only four colors to their skin (Epidermis): red, black, red-black, andyellow. Skin color results from a gene locus with three possible alleles: ER, EB, ande. ER and EB are both dominant to e but not to each other. Yellow skin results froma homozygous recessive genotype and red-black skin results from genotypes heterozygous with ER and EB. If a red dragon and a black dragon produce a yellowdragon what are all their genotypes? What other colors would be possible for the yellow dragon’s siblings?

If a red female dragon produced a yellow child what color male dragons couldNOT be the father?

A red-black pink-eyed dragon and a yellow white-eyed dragon produce children.What would be the expected phenotypic and genotypic ratios of those offspring?

Most dragons breathe fire but some cannot, and these latter are mostly males. Needless to say, this puts a real crimp in their ability to destroy villages and what not! Lack of fire-breathing is sex-linked (F=fire and f=no fire). If a fire-breathing male and a fire-breathing female that had a father that could not breathe fire (How did he ever find a fire-breathing mate?!) produce offspring what kinds could they produce?