I know i posted this in twilight Q and A, but i thought i would post it here too, seeing this is a science related question!
The blood goes through through their viens. That's what bella noticed one time after edward hunted, he had a red flush added to his skin.
The venom uses the blood to produce energy for their body. it's just the same with humans, we need food and water or otherwise we will have no strength to do anything, to thrive. It's the same with a vampire. That's why a newborn vampire is stronger than the decade old vampires.
Here, i got the Q & A from the personal correspendence
Q: If the vampires don’t have blood, then where did it go? Did it just dry up? Evaporate? Or were they nearly drained of it by the one who changed them?
A: The blood left in a newborn vampire’s body is used–burned like fuel, the same way the blood they drink from others is used for fuel. Here’s an analogy: think of it as the fat stores in your body. You’re still eating, but you use those fat stores up, too, over time (though not always; more’s the pity, so the analogy isn’t perfect unless you are successfully dieting). That blood left in them is used slowly over about a year.
wow personal correspondence! how did you manage that!
ok, so that explains where the human blood goes (superficially).
but my question is this - edward and jasper guzzle down litres and litres of blood inorder to be around humans and bella. obviously that blood has to go somewhere.
People argue that the blood is "burned up to create energy" or that it is converted into "vampire venom" or "other ejaculatory fluids "
but my problem is this:
why do vampires need an energy source? their cells would be dead, hence cellular respiration would not occur, thus there would be no need for energy for their body, and NO NEED TO EAT/DRINK BLOOD!
or are their "cells" alive in some form? do they have "living dead" cells that do require something from the blood - the hemoglobin perhaps?
hence the blood is then "burnt up" to produce energy for the "living dead" cells.
but here is the problem with that twiliverse explanation:
mater is neither created or destroyed, it is merely converted into something else. that is the first rule of chemistry.
what is the blood converted into after it is "burnt up?" Vampires do not do human functions such as defecate hence it could not be converted into something similar to urine or feces. Vampires do not need to breathe - hence it couldn't be converted into some gaseous form. they do not sweat - so it could not leave through the skin. they would need to rid themselves of the waste products of the blood-to-energy conversion, otherwise it would buildup in their body and they would become bloated (hence their bodies would change - which is not possible)
The venom and "ejaculatory fluids" idea worked - for like 5 seconds. because for the amount of blood the vampires consume - they would have to be spitting a river of venom, or for males either having quite a few wet dreams (even though they cant sleep?) or spending quite a bit of time behind the bathroom door "reading magazines"
and then there comes the question of female vampires!
if anyone has an explanation for this question (that has stumped me for years) either explained in terms of science or (twiverse psuedo-science) please let me know!
it would be much appreciated!