In Drosophila, the genes b, c, and sp are linked and in the order given, the distances being b-c = 30 m. u. and c-sp = 20 m. u. These intervals exhibit 90% interference. How many double crossovers would be recovered in a three-point cross involving b, c, and sp out of 1000 progeny?

Explanation:

Double cross over or three point test cross is helpful:

Interference is the physical phenomenon in which crossing over of a gene suppresses its neighbouring gene to cross over due to the physical property of genes

In the given question:

Distance between b-c = 30 m.u.

Distance between c-sp = 20 m.u.

Interference(I) = 90%=90/100=0.9

Progeny = 1000

DCO stands for double cross over  

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.

succession returns a disturbed

ecosystem to a more stable state. this is also classified into two (2) types:

primary succession and secondary succession. the primary succession arises when

a new land is transformed and a bare rock has been exposed providing an environment

that can be occupied for the first time. while, secondary succession occurs

when a previously occupied environment was disturbed that kills much of all its

community

explanation: