What do invertebrate jellyfish lack that all other fish possess?

When mendel crossed a true-breeding short plant with a true-breeding tall plant all the offspring were tall. which term describes the gene for tallnes?

Organisms that successfully adapt will leave to grownone of the above

Guinea pig coat color is determined by a single gene. the allele for black coat color is dominant to brown. in a cross between twoblack-haired guinea pigs, 20 offspring are born. if both parents were heterozygous, probability would predict that approximately howmany of the 20 offspring would have brown hair?