Which structural layer of blood vessels is most responsible for maintaining blood pressure?

According to the big bang theory, after the "bang," the universe remained dark until about  300,000 yearsone billion yearsthree minutesthree billion years  later, when neutral atoms began to form.

2. given that most biochemical (other than coal) rocks react with hydrochloric acid, what does that tell you about organisms?

Agene pool: a) is the collection of all the alleles found in a single species b) is the collection of all the alleles found in a single population c) is the collection of all the chromosomes found in a single population d) is the collection of genes in a species that allow the individuals to swim