What are two body systems that are used when shooting an arrow and how are the used?

Which best explains why there are 64 possible codons in the genetic code and only 20 amino acids that make protiens of living organisms on earth

Which of these substances does not protect against invaders in the nonspecific immune response? a. saliva b. mucus c. tears d. urine

In order to study genetic mutations, scientists must study genetic material. which statement describes the genetic material scientists are most likely studying? a) they study alleles that contain chromosomes, which are rna.b) they study alleles that contain genes, which are chromosomes.c) they study chromosomes that contain genes, which are dna segments.