It's not that common actually quite rare because gray eyes are less than 1 percent of the earth population. Being that blue eyes and black hair is considered genetically impossible gray eyes are lighter, which makes it even more most likely impossible.
Fun fact: 10,000 years ago blue eyes didn't exist they are a mutation and everyone with blue eyes is technically related.
Answer:
It is important because plants would not be able to produce food for themselves, so the plant would die. Animals that feed on plants would not be able to survive, and animals that feed on other animals would die too because they would not have any food.
DNA carries the instructions in for of genes.
This individual is heterozygous dominant for that height trait.
Explanation:
In Mendelian Genetics the letters in uppercase are for dominant traits and those in lower case are for recessive trait.
An individual has 2 alleles for a gene one from either parent. The dominant allele express the phenotype according to the law of dominance. Individual could be either heterozygous that is both the dominant and recessive traits' allele are present in its gene or homozygous dominant in which both the alleles are dominant.
eg: GG (dominant homozygous)
Gg (Heterozygous dominant)
The individual with genotype Gg for a height will have dominant allele expressed which will mask the effect of recessive gene. The phenotype will be of dominant trait.