In a reciprocal cross, we try to determine whether a trait is sex-linked Or not... One thing I couldn't understand was that, why are parents of contrasting genotypes involved? Does that mean that at one time, female parent has the particular trait we are that interested in and at the other time, the male parent has that particular trait?(please correct me if I am wrong) and if that's so.... Then, why is that? I mean what is the purpose of doing that?

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    – tyersome
    Oct 17 '20 at 4:43
  • $\begingroup$ I have found that when learning about a new area starting with a relatively accessible and reliable source like Khan Academy is very helpful. Wikipedia is also generally a good starting point and you can then check their references. Online platforms called MOOCs offer free (or very low cost) courses on a wide variety of subjects — two I am familiar with are Coursera and edX. Finally, textbooks with a good level of detail are also freely available online e.g. from NCBI. $\endgroup$
    – tyersome
    Oct 17 '20 at 4:44
  • $\begingroup$ I'd suggest doing even a limited amount of background research, or at least draw out some hypothetical crosses for yourself to see what happens. $\endgroup$ Oct 29 '20 at 19:20