NS FL 3 Bio Question

[sirromta]

Advertisement - Members don't see this ad

Can someone please fill me in onto how they may recognize this is a Trisomy?

 

[deleted1076141]

Each region of darkness represents an X chromosome. Notice that, for the offspring, the bottom region is about twice as dense/dark as it is on either parent. That means an extra X chromosome is present, ergo, trisomy.