How individual tissues coordinate to perform complex tasks (like respiration or digestion).

"Animal Physiology: From Genes to Organisms" (primarily known as the textbook by Sherwood, Klandorf, and Yancey) is built around the .

This "bottom-up" perspective helps explain why an animal functions the way it does, linking microscopic instructions in DNA to the macroscopic behavior of the whole animal.

How these internal processes allow the organism to survive and adapt to specific environmental stressors (like extreme heat or high altitude).

How specific gene expressions trigger the production of proteins and enzymes.