What are FOUR ways by which the heart rate can be changed? hormones
chemicals
age
sleep
ions
rest
autonomic nervous system

Which word can describe a person's gender identity? a) female b) intersexual c) asexual d) androgynous

Which statement best illustrates that problem solving can create new medical devices? robert hooke was in charge of verifying the information that was sent to the royal academy. william harvey did experiments with apes to learn about the circulatory system. the stethoscope was invented because the physician did not want to put his head on women's chests to listen to their heart and lungs. anton van leeuwenhoek was a very curious man and looked at just about everything under this microscope.

Why do rna viruses appear to have higher rates of mutation? a) rna nucleotides are more unstable than dna nucleotides. b) replication of their genomes does not involve proofreading. c) rna viruses can incorporate a variety of nonstandard bases. d) rna viruses are more sensitive to mutagens.