Answer - Blood Flow
Reasoning - Insulin is used through out and mainly in the blood stream which relies it to stabilize through out the flow of the body
The lungs need to remain elastic so they can<span> effectively move oxygen into the body and carbon dioxide out of the body</span>
The testes are contained in the scrotum and are composed of dense connective tissue containing around three hundred internal compartments called lobules. Each of these lobules contains a number of coiled, tiny tubules where the sperm are produced. Testosterone is produced in cells located in between the lobules
(lol weird question)
The first to do so was Leonardo Da Vinci
