Why does dna use thymine instead of uracil?

Isolated volcanic peaks on the ocean floor are

Anormal appearing couple is found to be heterozygous recessive for albinism both have the genotype aa the gene responsible for albinism is recessive to the normal pigment-producing gene what are the changes of their children being albino

Aragonite shells of clams, snails, or scleractinian corals may be preserved unaltered in cenozoic deposits, but they are generally dissolved or recrystallized in older deposits. true or false