Replicant - Organic or Mechanical?

Organic or Mechanical?

Although the press kit released to the media for the film explicitly defined a replicant as, "A genetically engineered creature composed entirely of organic substance", a question commonly posed is the physical make-up of the replicants themselves. In the opening crawl of the film, replicants are said to be the result of "advanced robot evolution." The crawl also states that they were created by "genetic engineers." Characters mention that they have eyes and brains like humans, and they are seen to bleed when injured (although they can take a lot more damage than humans can). The film explicitly shows that at least their eyes are created and stored separately, so there must be some "assembly" required. An alternative explanation could be that they are cyborgs, having both human and machine parts. That the (apparently) only way of telling a replicant from a human is to ask a series of questions and analyse emotional response would suggest they are entirely, or almost entirely, organic. If they had any significant level of non-organic parts then something as simple as an x-ray scan would show them not to be human (unless their creators designed the non-organic parts to have almost exactly the same structure and density as the organic components they were replacing, which would be both infeasible and highly improbable but not completely out of the question).

The original novel makes mention of the biological components of the androids, but also alludes to the mechanical aspects commonly found in other material relating to robots.

In May 2012, Ridley Scott confirmed that the replicants were biological in nature, and contrasted them to the androids in the Alien series. "Roy Batty was an evolved... He wasn't an engine. If I cut him open, there wasn't metal, he was grown... and then within twenty years you get the first bill not passed in the Senate where they applied for replication of animals, sheep and goats and cattle and animals and they turned it down, but if you can do that, then you can do human beings. If you go deeper into it and say 'Yeah, but if you are going to grow a human being, does he start that big and I've got to see him through everything?' I don't want to answer the question, because of course he does... Ash in Alien had nothing to do with Roy Batty, because Roy Batty is more humanoid, whereas Ash was more metal".