A plant of genotype C/C ; d/d is crossed to c/c ; D/D and an F1 testcrossed to c/c ; d/d. If the genes are linked, and 20 map units apart, what will be the percentage of c/c ; d/d recombinants

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.