What does excessive algae on water cause?
When algae cover a river surface, it causes depletion of oxygen in water. This is known as .

Eutrophication

Explanation:

Greek word meaning "well-nourished"

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.