How has Shakespeare added tension between the characters in Act I, Scene 3, of The Merchant of Venice?

Act I, Scene 3, is when the stakes are set up for Shylock's loan to Antonio. Shylock loans Antonio 3,000 ducats, which Antonio gives to Bassanio to finance his pursuit of Portia. Shylock lends the money without interest, with the stipulation that Antonio sign a contract allowing Shylock to extract a pound of his flesh should he be unable to repay the debt. Though Shylock acts as though this part of the bargain is just a joke, Bassanio, and most audience members, are concerned. After all, at the end of the scene they get the deal notarized, making it legally binding. Additionally, most of the scene involves Antonio and Shylock arguing about interpretations of Bible verses, their different moneylending practices, and their conflicts with one another's religion. This is also the scene when Shylock gives several asides to the audience that explain his hatred of Antonio and Antonio's cruel treatment of him in the past. All in all, the scene is full of interpersonal strife that culminates in a dangerous loan that provides the main conflict of the play.