Definition: A contractile form of tissue which animals use to effect movement.

Alright class, settle down now, let’s take a peek, At a word that’s important, simple and sleek! We’re talking about “muscles,” let's give it a try, To understand what they do, way up high. The dictionary gives us a clue, you see, “A contractile form of tissue, for you and for me!” Let’s break that down slowly, nice and slow, So the meaning truly starts to grow. "Contractile" – That's the key, it’s true! It means they can shorten, like pulling through. Think of a rubber band, stretched out with glee, Then squeezed tight - that's how muscles agree! They tighten and loosen, quick and bright, Helping us move, with all their might. From running and jumping, to lifting a plate, Muscles are working, it’s truly great! “Tissue” – Just like skin or bone you see, It's part of our body, for you and for me! A building block, inside so neat, Helping us function, can’t be beat! So, "muscles" are these tissues that move , Using contraction, a powerful groove. They help animals – like us, it's true - To do all the things they need to do! Does that make sense? Any questions you might pose? Let’s discuss this further, and really know our prose!