I think student answers do encourage student questions especially if it on a topic that they can discuss and have opinions on. If we could encourage the students to think of their different opinions as valuable, perhaps they would be more likely to share them. This could be used to focus students before asking them to apply a concept. Any question that relates to something they see everyday but might have overlooked. For instance, during our trophic level lab the students go to the lake here on campus.
Physical plant puts a blue dye in the water that helps cut down on algal growth.
One of the TAs asked the students if they thought it was a good thing or a bad thing and his class got into a heated discussion. You can ask any of those students about trophic levels and the condition of our lake on campus and they can talk for quite a while. It is so easy to just rattle on and not stop and find out if the students have questions. I love to hear my non-majors talk about there things to their friends outside class. Nursing student questions are very helpful in a computer applications class.