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So, in a recent discussion I had there were a few interesting points raised about Wolverine - primarily how contradictory having an adamantium skeleton is.
Firstly; blood. Bone marrow is the source of blood generation (basically), so the fact that his skeleton is encased (correct me if I'm wrong) in adamantium suggests that there is no way for him to replenish his blood, which would heavily impact his ability to heal, though that would likely be the least of his problems.
Secondly; his claws. Controlling the extension and retraction of his claws would require some form of connection via tendons, though yet again, if they were completely encased, this would mean either the connection to the muscle and tendons was severed, or, they too were coated in adamantium.
Is there some explanation for this in universe? Or any kind of explanation that might allow this to make sense (other than "I'm a comic book legend, not a doctor")?