<span>The biological term for such organisms is "deuterostomes". Those who's first opening is the mouth are called protostomes.
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Answer:
The three genes in coupling are in repulsion.
Explanation:
Coupling happens when the dominant alleles and the recessive alleles are on the same homologous chromosome, while the repulsion happens when one chromosome has one dominant allele and one recessive allele and another homologous chromosome also has dominant and recessive alleles.
If the progeny has:
nb+ ls+ a/nb ls a ⇒ nb+ ls+ a
nb ls a+/nb ls a ⇒ nb ls a+
Where nb+ ls+ a is the dominant alleles and nb and nb+ is in middle.
ls+ nb+ are on the same chromosome (both dominant)
ls nb are on the same chromosome (both recessive)
ls nb, these two are in coupling with each other, but ls+ and a are on the chromosome and ls+ or nb+ are dominant, while nb+ and a are recessive on form a, thus, ls and nb, they are in repulsion with a.
That’s the periosteum. it’s a hard membrane, which muscles and ligaments are attached to, under which blood flows through the bone
