Answer:
an S strain and mix it with cells of an R strain
Polygenic is a<span> </span>trait<span> that is controlled by a group of </span>nonallelic <span>genes. </span>For example, humans can be many different sizes. Height is a polygenic trait, controlled by at least three genes with six alleles. If you are dominant for all of the alleles for height, then you will be very tall. ... Skin color is also a polygenic trait, as are hair and eye color. A trait that is controlled by a group of nonallelic <span>genes
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Answer: Ectotherm
Definition: An animal that is dependent on <u>external sources of body heat</u>.