Question: Q: Rna and dna are types of what biochemical compounds containing the elements carbon, hydrogen, oxygen, nitrogen, and phosphorus? Choices: - hormones - nitrous acids - amino acids - nucleic acids A:
Answer: nucleic acids

Question: Q: Which blood cells serve to defend the body in various ways? Choices: - helper blood cells - blue blood cells - red blood cells - white blood cells A:
Answer: white blood cells

Question: Q: What system consists of glands that secrete hormones into the bloodstream? Choices: - Respiratory system - nervous system - Muscular system - the endocrine system A:
Answer:
the endocrine system