Explain the mode of inheritance governing coat color by determining how many gene pairs are involved and which genotypes yield which phenotypes.

Explanation:

Surprisingly, until recently, not much was known about the genes that control melanin production. 6 were known (MC1R, TYR, OCA2, SLC24A5, MATP and ASIP) and 17 more have been recently identified (DTNBP1, GPR143, HPS3, KITGL, MLPH, MYO5A, MYO7A, SLC45A2, TYRP1, ERCC6, GNAS, HERC2, IRF4, OBSCN, SKC24A5, TPNC2 and MITF), all of them directly or indirectly related to the process of melanin formation and distribution. Since there are so many different genes, if we count all the possible alterations, many different color variants can be produced.

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.