Tom, being a scientist (as well as an educator, an entertainer and - as I intend to demonstrate to the world in the next few days on this blog - a levitator) was able to tell us much, much more about quarks, and indeed about particle physics.
Quarks are sub-atomic elementary particles, fundamental constituents of matter. They are literally everywhere. Like many things in physics, they have quirky, almost poetic names - actually 'flavours' to physicists: Up, Down, Strange, Charm, Top and Bottom. Up and Down quarks were discovered in 1968, and the most recently discovered were Top and Bottom, in 1995. They are so small that they cannot be directly observed - in fact the infinite littleness of quarks is as hard to grasp as infinity itself. Everyone knows that atoms are small. Well, atoms are made from protons and neutrons, and protons and neutrons are made from quarks - that's to say, quarks are a great deal smaller than atoms, so small that it has been posited that a quark could travel through a mile and a half of lead before colliding with any other matter at all. That's very small indeed.
If quarks are a little hard to take in, help is at hand. There is a quark song. It's called Strange Charm, written and performed by Hank Green of vlogbrothers, and my only warning before you click Play is that if you watch the YouTube video more than once, the tune will lodge itself like a virus in your brain and will emerge over the next few days, perhaps longer, as an irritating hum. If it emerges complete with words, you'll definitely have learned something though – Strange Charm does for quarks what Eric Idle did for the galaxy.