Which of the following is a conceptual model that represents the flow of energy through an ecosystem? a. inheritance b. food web c. infiltration d. circulatory system

What substance acts to prevent sudden ph changes in bodily fluids?

Drag each tile to the correct box. the body monitors the levels of oxygen in the blood to regulate breathing. isabel is running in a marathon and is near the finish line. she feels out of breath. how will her nervous system work to generate a reaction? arrange the tiles in chronological order. isabel's breathing rate increases. sensory receptors in the arteries detect low oxygen levels. the brain sends signals through motor neurons. sensory neurons generate an impulse. the central nervous system relays an impulse to certain brain regions.

The most famous fossil called archaeopteryx is which of the following? a dinosaur a fern a fish a bird