16. Which of these provides most of the oxygen in Earth's atmosphere?
coral reefs
rainforest plants
ocean phytoplankton
continental grasslands

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

the endomembrane system i think

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

here's your answer.

where in your body is there an enzyme that does function at a high or low ph? what is the name of that enzyme and its function?