The english language is a bit of a nightmare. Words (and bits of words) borrowed/inherited from all over the place.
To borrow/paraphrase a bit from Monty Python (the dead parrot sketch).
"'Is metabolic processes are now 'istory! 'E's off the twig! 'E's kicked the bucket, 'e's shuffled off 'is mortal coil, run down the curtain and joined the bleedin' choir invisible!! THIS IS AN EX-"