Wich type of matter is always made up of only one kind of atom

Elements

Explanation:

"Elements are substances, forms of matter and gasses that are made up of only one type of atom."

Panico. (2012, September). The Atomic Model and Matter. Retrieved December 15, 2020, from https://odysseyk12.org/hs/teachers/panico/pdf/atoms/atoms.html

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.