Most of the water reaching the collecting ducts is not reabsorbed
So, the Sun's light takes about 8.3 minutes to reach us. This means that we always see the Sun as it was about 8.3 minutes ago. ... The nearest large galaxy to us, Andromeda, is 2.5 million light-years away. So, we see Andromeda as it was 2.5 million years in the past.
I believe the inability to make saliva would affect digestion drastically. The first phase in the process of digestion comes with saliva - it breaks down some substances in your mouth, because it contains amylase which helps during this process. If it weren't for saliva, you probably wouldn't even be able to swallow food - and even if you did, it would be almost impossible to break it down in your body.
