In a high school science class, the teacher has a question for her students.
“Who can tell me which organ of the human body expands to 10 times its usual size when stimulated?”
The class is silent.
“Lisa?” the teacher says. “Do you know the answer?”
Lisa blushes furiously. “I think this question is inappropriate and I’m going to tell my parents about it.”
The teacher shakes her head and asks the question again.
Finally, Brendan raises his hand.
“The iris of the human eye expands to 10 times its size when stimulated, ma’am.”
“Correct,” says the teacher. “Lisa, I think it’s best if you start doing the assigned reading for this class. Otherwise you’re going to end up very disappointed when you’re older.”