"Biology Instructor" joke

Mr.
Cikoch was a biology instructor at a snobby suburban
girl's junior college. During class one day he asked
his student, "Miss Simison, would you please
name the organ of the human body, which under the
appropriate conditions, expands to six times its
normal size, and define the conditions."
Miss Simison gasped, and then said, "Mr.
Cikoch, I don't think that is a proper question
to ask me. I assure you my parents will hear of
this. "With that she sat down red-faced.
Mr. Cikoch then called on Miss Hakar and asked
the same question. Miss Hakar, with composure,
replied, "The pupil of the eye, in dim light."
"Correct," said Mr. Cikoch. "And
now, Miss Simison, I have three things to say to
you. One, you have not studied your lesson. Two,
you have a dirty mind. And three, you will some
day be faced with a dreadful disappointment."