Frogs exchange gases through their skin and the lining of their mouths. This exchange of gases is referred to as respiration. During the larval stage in frogs development, it lacks functional lungs but they can take in oxygen through gills which are in process of metamorphosis.
The gills take in oxygen when water is being passed over them. Once lungs are mature, they lose their gills and are able to bring in oxygen through lungs.
They rely on lungs to breath when they are active and they need more oxygen than what skin respiration alone can provide.
Although they have oxygen, most of their respiration occurs through the skin.
It measures the total amount of Carbon dioxide

and Methane
Answer: ecosystem 1: oarweed, rockfish
ecosystem 2: nudibranch, sponge, otter,
ecosystem 3: sea urchin
Explanation: based on my research this is what i could put together
Hi,
If you meant ‘hypertonic’, then the missing words are ‘higher’ and ‘outside’.
If you meant ‘hypotonic ‘, the missing words are ‘lower’ and ‘inside’.
Hope this helps!