The function of the nervous system is to A) help protect the body from disease. B) bring oxygen, nutrients and hormones to cells. C) control growth, development, metabolism and reproduction. D) coordinate the body's response to changes in its environment.

the leaf is an organ of a typical plant, and the main functions are to complete photosynthesis and allow the plant to exchange gas, just like how we have the respiratory system. leaves have the stomata, which collects maintains co2 and o2 levels. this is necessary for cell metabolism. the leaf also collects sunlight using chloroplasts. succinctly, leaves own a pivotal role in sustaining plant life.

it means there are 3 atoms of oxygen

level 4 to level 2 : ))