Killer midterm

My students bombed my midterm exam last week. They all complained it was hard, which I wouldn't have thought much of but then Kevin looked at it and thought it was very detailed for nonmajors, too. It's become hard for me to gauge which question is hard because they're all the same to me, although I do have a tiny idea, especially on my more tricky questions. When I'm choosing between two questions that cover the same concept, I inevitably choose the harder one. I have to curb that tendency.

My average was a 25 out of 50, so they got a very generous curve. I remember getting a 30/100 on a physics final once. I felt that I had gotten nothing right on the test, that I had failed the class. Turns out the 30 was a C grade. I was relieved, of course, but I also wondered what was the point of that physics class. The teacher had made it so hard that students like me either knew nothing but passed anyway or knew something but thought I knew nothing. I definitely don't want to be like that guy.

Only the final exam is left now. I always go easier on the final because the students have to deal with their other finals and also all the information from the beginning of the semester. Speaking of the semester, boy does it drag on. I think I prefer the quarter system. Here's a sampling of my tough questions:

1. What is the final electron acceptor of the noncyclic electron flow in photosynthesis?
a. H2O
b. NADP+
c. O2
d. ATP

2. In snapdragons, red flower is incompletely dominant with white. Straight leaf is dominant over curly leaf. If a pink plant with curly leaves is crossed with a white plant with homozygous straight leaves, what are the chances of producing a white, straight-leafed plant?
a. 1 out of 2
b. 3 out of 16
c. 3 out of 4
d. 1 out of 4

Did you get it right?