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evidence is discovered
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.
The two tiny structures located in the cytoplasm near the nuclear envelope at the beginning of prophase are called <u>centrioles.</u>
The risk of lung cancer death is no different between medium, low, and very low-tar cigarettes.
People who smoke low-tar cigarettes compensate the lack of tar by changing their breathing habits, for example, they will take deeper drags or hold the smoke in for a longer period of time, basically negating the supposed " low-tar" effect.
Independent assortment states that all alleles are inherited independently of other alleles. This helps diversity because it helps to further the randomization of traits. If traits were always inherited together, as a "package deal", there would naturally be less diversity than the situation that exists. For example, one may never see a person with blue eyes and brown hair if the alleles for the two traits, hair and eye color, were inherited together. However, it is worth noting that there is "genetic linkage", meaning full or partial violation of independent assortment among certain trait groups.
There are 46 chromosome in a normal human diploid cell, 23 inherited from the mother's egg and 23 inherited from the father's sperm.