<span>An amphibian that lacks lungs and breathes entirely through its skin would have to be smaller than an amphibian with lungs so that the small oxygen intake correlates with
the small surface area of the amphibian. This would then allow it to breath efficiently.</span>
Gametes are the genetically different kind of cells which are produced as a result of meiosis. Meiosis is a reductional division in which the chromosomes are reduced to half. Genetic variation in the gametes is due to crossing over between two non-sister chromatids of a homologous chromosomes during meiosis.
Answer:
Gulls, since they are the only predators shown for the green crabs.
A constant variable would be an element that remains unchanged and constant throughout the course of the experiment / investigation.