system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: what does the spleen do with old/unviable red blood cells after it has filtered them from the bloodstream?
gpt
Healthy red blood cells simply pass through the spleen by virtue of their shape and ‘youthful’ flexibility making it possible to pass through a series of small “passages”. Damaged, malformed or otherwise misshapen and nonconforming red blood cells are caught in that network and broken down by white blood cells.