What happens when you change the material through which a wave travels?

Changing the material will speed up or slow down the wave depending on the index of refraction of the material.

At each level of organization—cells, tissues, organs, and organ systems—structure is closely related to function. ... The structure of the heart reflects its job of pumping blood throughout the body, while the structure of the lungs maximizes the efficiency with which they can take up oxygen and release carbon dioxide.

Explanation:

Got the answer from

https://www.khanacademy.org/science/high-school-biology/hs-human-body-systems/hs-body-structure-and-homeostasis/a/tissues-organs-organ-systems