[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Novel student errors
Now that I have the honor of grading papers, I get to keep track of some
interesting student errors.
One exam question asked students to calculate what percentage of
ionizable amino acid side chains would be ionized at a given pH. I was
rather surprised to see a couple answers like 1,000% and 2,000%, but
actually these were fairly tame errors when compared to the one person
who claimed that 700,000% of the side chains were ionized.
The next two are from papers on protein structures.
Unlike traditional macroscopic objects, it appears that amino acids have
the amazing ability to be two places at once:
"The hydrophilic N-terminal region of the polypeptide fits into the
minor groove [of the DNA], while the third helix [at the other end of
the protein] fits into the major groove. Many arginine residues,
including arg 3, arg 5, and arg 53, can be found in both of these
segments."
And my favorite so far:
"The beta sheet twists through the core of carboxypeptidase in the shape
of a three-dimensional plane."
--
Eric Bennett ( [email protected] ; http://www.pobox.com/~ericb )
Department of Chemistry, Cornell University
377 S.T. Olin Chemistry Lab
Mr. Gates needs a memory upgrade.
-Mitchell Pettit, Executive Director, ProComp
===
This message was sent to mph-humor. No guarantees of actual humor are
provided. Archives and instructions are available from
<http://www.pobox.com/~mph/humor/>.