Which part of the body takes care of removing liquid and gaseous wastes from the body?
Primarily, the colon, kidneys (food digestion) and the lungs (respiration).
The colon is the final stage in the digestive process, which recovers liquid which is then processed by the kidneys. The kidneys do the actual separation/concentration of waste fluids for excretion.
The colon also collects and expels any gaseous wastes and by-products from the digestion process. The lungs are also a key organ for the removal of waste gas products from respiration.
and for a simpler explanation: