Here, you have a case of codominance.
You know that because they tell you that in the presence of both alleles (purple and white) you have a light violet. No one is dominant over the other, both appear as a combination of alleles.
Purple: P
White W
A heterozygous plant has PW alleles.
PW x PW = PP PW WP WW
25% chances of PP (deep purple)
50% chances of PW (ligth violet)
25% chances of WW (white)
300 BC by Greek philosophers
The atomic level would be melting point
They can either be protons (positive) or electrons (negative)
Primary succession is beginning.
Primary succession is when a disaster destroys the environment, leaving no soil and no organisms left. This is evident by the bare rock. Lichens are a pioneer species, meaning they are one of the first organisms that show up.