This actually happened at Harvard University.
In a biology class, the professor was discussing the high glucose levels found in semen.
A female freshman raised her hand and asked, “If I understand, you’re saying there is a lot of glucose, as in sugar, in semen?”
“That’s correct”, responded the professor, going on to add statistical info.
Raising her hand again, the girl asked, “Then why doesn’t it taste sweet?”
After a stunned silence, the whole class burst out laughing, the poor girl’s face turned bright red, and, as she realized exactly what she had inadvertently said (or rather implied), she picked up her books without a word and walked out of class, never to return.
However, as she was going out the door, the Professor’s reply was classic.
Totally straight-faced he answered her question…
“It doesn’t taste sweet because the taste buds for sweetness are on the tip of your tongue and not the back of your throat. Have a good day.”