Possible Clues:

• It's used in jelly and adhesives
• Clear substance used in jelly
• It's used to set jellies
• Gee! That's what'll make one a big stiff about the classics
• Sticky substance obtained from boiled animal tissue
• Setting agent
• Exclamation of surprise about language that's used in films
• Gee! Taking a classical language can be sticky
• Animal-based gluey substance used in cooking, photography etc
• Made a gentile make jelly