Echinoderms, like chordates, are deuterostomes and are therefore thought to be the most closely related of the major phyla to the chordates
Serial Monogamy is the behavior n mating in which one male breeds with a female for a certain period of time and then finds a different mate the following mating season. It is defined as a succession of short monogamous relationships or <span>the practice of having a number of long-term romantic or sexual partners in succession.</span>
The cross between Dd egg-snail and a dd s snail mate will result in snails with genotype 1/2 Dd:1/2 dd and phenotype all right-coiling.
<h3>What is a genotype?</h3>
The genotype refers to the allele combinations that can be found for one or more loci in an individual.
The phenotype refers to how the genes and alleles interact to produce a physical trait in an organism.
In this case, one parent can produce two types of gametes (D and d), whereas the other parent can only produce d gametes.
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Dinosaurs became common on land