Over the past 3.5 billion years the photosynthetic processes of cyanobacteria added a significant amount of this gas to the atmosphere, making possible for life as we know it to evolve?

The most effective way to provide children with safety messages is to

Baroreceptors in the aortic arch and carotid bodies are mechanoreceptors that respond to the stretch that occurs in these arterial walls with changes in blood pressure. if pressure changes rapidly, the baroreceptors initiate a feedback mechanism that reduces blood pressure; however, if pressure changes slowly, as in developing hypertension, the receptors do not respond. given this information, the baroreceptors are most likely which type of receptor?

Scientific research about the nitrogen cycle and water quality is mostvaluable to human populations with: afew sources of electricity.b. few sources of fresh water.c. large coastal populations.d. large amounts of farmland.