A frog's lungs don't work that well, but since it's skin is so thin, oxygen and carbon dioxide can pass trough it.
The function of the respiratory system is to exchange two gases: oxygen and carbon dioxide.
Hope this helps :)
Conservationists occasionally light forests on fire to control wild fires. By occasionally burning material (like leaves, branches, etc), those materials cannot build up and cause large and uncontrollable fires later.
Lysozyme is the enzyme in tears
