Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
Among its collection of parts, this movie has a pop singer (Sarah Michelle Geller) who is owned by a nasty gangster, and a doctor (Kevin Bacon) who desperately tries to save the love of his life from a venomous snake bite (even though she married his best friend). Once again it's the old snake bite device, beloved of lazy screenwriters everywhere. (They also use the pedestrian killed by a car cliche to get rid of somebody quickly in the movie, and a really cheezy edge of a building cliff-hanger.)
Julie Delpy plays the woman who gets snake bit. She's some kind of toxicologist who is trying to cure hemophilia with snake venom. When she is handling and milking a venomous snake she manages to get bitten. This time they don't use the old snake bite device to get rid of somebody, they use it to add some of that all-things-are-connected 6-degrees-of-separation from Kevin Bacon movie mysticism that won Crash a gold statue a few years earlier.
Back to the snake bite - the hospital was conveniently sent the wrong anti-venom so Delpy will die if she doesn't get a blood transfusion, but her blood type is so rare that the hospital doesn't have any on hand and neither does any other place in town. But when intrepid Doctor Bacon watches a TV interview with pop star Geller, he learns that she has the same rare blood type. He goes to heroic lengths to finally get Geller's blood (something those Buffy the Vampire Slayer vampires could never do) and Delpy survives.
Delpy seems to be handling a live snake in the lab, but I can't tell what species it is. Dr. Bacon calls it a "Russel Viper" (he means "Russell's Viper) but it looks nothing like one,. The close-up of a snake being milked for its venom was certainly filmed somewhere away from the actors. The snake that bites her arm is fake, of course, probably CGI. When we see a close-up of the snake biting her it looks completely different from the snake she's milking - in size, pattern, scales, you name it. But that doesn't matter really, because it probably wouldn't be noticed by anybody except a snake movie nerd watching in slow motion to get a screen capture to put on a silly web page. (You're welcome.)