Off to a great start

We discussed major groups of biological molecules today. We had an in-class (ask all the questions you want) "quiz" that asked students to report a favorite breakfast and "name a carbohydrate (chemical, not the food) found in this breakfast."
How many named food items?
How many wrote "lipids" "proteins" or "nucleic acids"?
Okay, so it's not that many. 3 wrote food items (including 2, eggs and bacon, that have almost no carbs,) 5 wrote the names of the other groups of molecules, and one wrote "nitrogen." That means of attendees, 86% wrote "sucrose", "starch", "lactose" or something else that made sense.
While it angers me (although it doesn't surprise me) that I have three students blatently not reading the question, it's the "nucleic acid" or "lipids" part that really bothers me.
These are students who, in the immediately proceeding 40 minutes, just learned (strike that, use "heard"), "there are four types of biological molecules," "these types are 1) carbohydrates, 2) lipids . . . .," "we're going to talk about examples, functions and special properties of each group. Let's start with carbohydrates."
It could be just a basic not paying attention problem. But I see this often enough that I'm really beginning to worry about the level at which logic breaks down. There are (seemingly intelligent) college students who, if told "there are three states in our region," would think "Texas" is a logical answer to "Name a city in Oklahoma"*.
These are the same students who fail to understand that something can simulataneously be an insect, an animal and a eukaryote.
How does one teach that level of logic to adults?

*Bad example if there happens to be a Texas, Oklahoma, but I don't think there is.