Pls only legit answers im gonna fail this class While gutting a fish, Nathan encountered an air-filled sac-like structure. What is the purpose of this structure in fish?

A.
It enables fish to breathe in water.
B.
It serves as a reserve space to store fat.
C.
It harbors bacteria that benefit the fish.
D.
It provides buoyancy to the fish.

I’m pretty sure its D

Good luck in class :)

Atp is is our little "pocket" of energy. of course, if you have too little, then it means you have too little energy, and you'll pass out. the way to not have enough, is to have no energy sources (glucose, fats, proteins). you can't have too many atp molecules. cycles like the krebs cycle produce it, but if you have too much of any substrate (or too little for that matter), the cycle stops and atp is no longer made (it stops until substrate levels are such that the process can go on). in any case, this is unlikely since atp is constantly hydrolyzed and remade, even while you're asleep. you won't have too much. if you have zero, you are dead or dying.