(19 Sept 2008)
Another embarassing mistake! In question #3: The third sentence
should read "How many different combinations of these bases
could you create if you had an RNA [NOT protein]
polymer strand that was four bases long?"
My apologies! If you answered this question correctly
for either RNA or for proteins I will give you credit.
(19 Sept 2008)
A minor mistake that I made: In problem #6, I told you that there
are 6 x 10^23 atoms of Al in one gram of Al. Actually, that's a little
bit wrong! There are actually 6 x 10^23 atoms of Al in one mole
(a unit) of Al, and around 27 grams per mole of Al. This means that
there are actually (6 x 10^23) / 27, or 2 x 10^22, atoms of Al
in one gram. This will not change your anwer significantly,
and you should feel free to do this problem either the slightly
wrong way I told you in the homework, or the correct way described
here.
(17 Sept 2008)
For problem #3: I wrote something that might be a little confusing.
I wrote that "although protein polymers are made up of many
fewer monomers than RNA polymers are...." This sounds wrong,
because you know that there are four different monomers that
are used to build RNA molecules, and 20 different amino acids
that are used to build proteins. What I meant is that protein
polymer chains have a smaller number of monomer units combined
together than do RNA polymer chains. In other words, proteins
might have hundreds to thousands of monomers chained together,
whereas RNA may have millions of monomers chained together.
For problem #4: I am not asking for detailed analyses of the compositions of these items -- just rough, ballpark estimates. In other words, what are the major components? Don't worry about the minor (trace) components.
Last modified 17 September 2008