What holds the two parts of a metal together?

All metals are made up of a vast collection of ions that are held together by metallic bonds. A metal atom has a positive nucleus with negative electrons outside of it. In a solid, each atom loses the outermost electron, which takes part in bonding.

Explanation:

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.