Do we ever wonder how flowers get their Colors?

Anthocyanin pigments, stored in the vacuoles of petal cells change color with pH (acidity). The Japanese Morning Glory, Ipomoea tricolor var. Heavenly Blue, changes color from purple to blue in the early hours of the morning A section of the petal (B) shows the transition in color. Notice the change in cell volume (C) and pH (D) accompanying the color change. This is a caused by the induction of a gene, NHX1 that exchanges sodium or potassium ions for protons and regulates lumen pH. 

In humans, these same genes regulate pH inside synaptic vesicles and appear to be important for packaging neurotransmitters for release, and clearing them from the synaptic cleft. Mutations are linked to autism, addiction, ADHD and XLMR.

Why is chemistry important for understanding the human body?

The universe and everything in it is composed of matter. Matter is anything that occupies space and has mass. The 92 naturally occurring chemical elements are the fundamental forms of matter. Twenty-six different elements are found in the human body. The continually ongoing chemical reactions in the body underlie all physiological processes of the body, including movement, digestion, the pumping of the heart, respiration, and sensory and neural processes.