What physiological adaptations a human would have to take if they were shrunken in size and lived underground?

Question

Hi, doing a report on the senario that Alice, in Alice in Wonderland , a 10 year old girl, shrinks to 1/100 of her size and ventures down a rabbit hole into the ground, where she discovers a new fantasy world. Remembering that Alice is a warm-blooded human being, what type of physiological adaptations would be needed to allow her to continually function normally uninterrupted so she can run, romp, and play with all her new friends and activities? Can you name any physiological adaptations and explain them in the anatomical sense, using examples from the major systems of the body? Thanks, need some help with this.

Answer 1

First a 10 year old girl weighs about 70 pounds. While a rabbit can weigh 7-10 pounds. That is 1/10 the size not 1/100.
Rabbits function quite well with all the usual physiology that a human has so except she needs to be smaller she wouldn't need different mechanical, physical, or biochemical functions. Many creatures vary by 10 fold. Compared to a horse we are 1/10 their size. (So to be 1/100 it would have to be a horse going down that hole.) Still no problem between their physiology. They all three, rabbit, child & horse eat, digest, excrete, respire, and react to stimuli equally well at their respective sizes using the same means.
Differences would come if the size change effected the ability to respire for example. If there could be no gaseous exchange in the lungs because there was no room to hold the fine structure of aveoli to provide enough surface to volume. This down in the range of a single cell. Cells have structure but not lungs. Gas crosses the membrane directly on that scale. Single-celled cell surface membrane has a sufficiently large surface area to volume ratio to act as an efficient gas exchange surface.
Crustaceans are at the size where the respiration shifts over to passive exchange through thin areas of their cuticle in smaller ones while larger ones have gills.