system
Given the following post, respond as if you're commenting on Reddit:
human
If both the liver and the kidney are filtering organs, what are their different responsibilities? Are there other organs that perform similar functions?

I know that the liver does about a million different things and secretes bile, while kidneys remove urea, but are there any overlapping functions?
gpt
Under the constraints of evolution, each organ it typically highly specialized to a specific role or set of roles. There are some redundancies in the body but implementing them is usually part of a pathological process. 

The liver acts to metabolize molecules to make them more easily excreted. Sometimes this detoxifies the molecule, sometimes the metabolite is more toxic than the original substrate. The liver also produces many proteins, clotting factors, helps regulate glucose, ammonia, and cholesterol levels, stimulates platelet production, and aids in the digestion process. 

The kidneys serve to help remove soluble wastes from the body. In doing so they also remove water from the body. They also serve as a monitor of your total blood volume, stimulating red blood cell production and/or water retention if necessary. Some drugs are metabolized and excreted through the kidney as well. 

Both the kidney and the liver are involved in the urea cycle, and in heme degradation, but their roles are sequential, not parallel.