Quiz on DNA. He calls is a so-so quiz on DNA. He says that one question is really, really, dumb. I disagree, I think there are several dumb questions.
I tried it and got a score of 19/19 in just under four minutes. This is misleading since you have to get every question right before continuing on to the next question. I had to anticipate what the authors wanted in order to proceed.
Try the quiz yourself before reading any further. There are spoilers below!
This quiz is harder than the average quiz. You have to know quite a bit about DNA in order to get all the answers correct. It seems to be aimed at college students although I suppose there are high school students who could answer all the questions.
On the handedness of DNA]. That does not inspire confidence.
The very first question is, "What is the shape of a DNA molecule?" The correct answer is, "DNA is a long skinny molecule." The answer they wanted was the answer to a different question; namely, "What is the shape of double-stranded DNA (two molecules)." (See the questions and required answers in the table below.)
The really, really, dumb question is #2. "What is the purpose of DNA?" There are many correct answers but the answer they want is definitely wrong, or at best incomplete. It ignores genes for noncoding functional RNAs and it ignores regulatory regions that control gene expression.
For Question #9 ("What is one of the component of a nucleotide?") the only acceptable answers are sugar, phosphate, and base. "Nucleoside" is not an acceptable answer even though nucleotides are just phosphorylated nucleosides. (Ribose is not acceptable either so if you are being picky the question should have asked about deoxyribonucleotides.)
Many prokaryotic genomes are circular but "circle" is not an acceptable answer for Question #12. You have to say "ring." Some prokaryotic genomes are linear; this has been common textbook knowledge for over 30 years. The answer is not correct.
"When DNA replicates, what enzyme unzips the parent strand?" I don't know what a "parent strand" is. What I do know is that unwinding at the replication fork is assisted by one of the subunits of the replication complex. This subunit has helicase activity. I suppose it's not wrong to say that DNA has to be "unzipped" by DNA helicase but it's not how I would word the question.
According to the authors of the quiz, there is only one acceptable answer to "DNA directly codes for which type of RNA?" It's not ribosomal RNA and it's not tRNA. Now I suppose you could quibble about the word "code" and assume that this only refers to protein-encoding genes but that's a stretch. It looks to me like the authors of the question don't know about any information content other than protein-coding genes.
The last three questions require you to have memorized two names (Chargaff and Okazaki) and to remember that DNA polymerase can only work in the 5′→3′ direction. That's asking a lot.
Is a quiz like this the best we can do to educate the general public and promote scientific literacy? Who made the quiz? Was it created by people who knew all the problems that I addressed above but decided that they should be ignored for simplicity? Or was it made by people who actually didn't know the correct answers but thought they did? It seems to me that the second possibility is more likely since there are lots of other examples of misleading scientific information being spread by amateurs on the internet—especially about evolution.