What three particles make up atoms?

The three main subatomic particles that form an atom are protons, neutrons, and electrons. The center of the atom is called the nucleus. First, let's learn a bit about protons and neutrons, and then we will talk about electrons a little later. Protons and neutrons make up the nucleus of an atom.

Explanation:

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.