I came to the conclusion half way through the immuno exam that the only way I was going to survive the post-exam anxiety was to not think about it. Actually, I have this nice rationalization about how the professors gave us absolutely no direction for studying, and the exam was written a bit erratically and may have completely missed important points (that I knew) while focusing on silly little things (that I may not have known) like whether the membrane attack complex uses C5b, C6, C7, C8, or if it uses C4a, C6, C7, C8. The latter incidentally, and I got it wrong. Same thing with convertases of the classical and alternative pathways.
So I made chocolate cake.
Then I came back to it, and now I see: How could I have been so foolish? The right answer was so easy to arrive at, and so completely necessary to a sound understanding of immunology!
After all, the pathway goes along the lines of:
C1 cleaves itself. C1s cleaves C2 and C4. C4 is now C4b. C4b and C2b make C3.
Meanwhile, C4b2b cleaves C3!
C3b joins C4b2b to be C4b2b3b...did we mention C5 yet? Well, OBVIOUSLY C4b2b3b cleaves C5, and now we have C5b, which clearly shows why the answer to the other question was C5b, C6, C7, C8, and C9. And since this was the classical pathway, that's why you were wrong. The alternative pathway uses C3bBb. That's a B, not a 2. (sheesh, get it right)
But I was a silly student and didn't realize that we were supposed to know the alphabet in this new, convoluted form. I just had it summarized in my notes as "Legos."
Probably it would help if our prof used something other than the detailed diagrams from our textbooks. Lecture becomes exponentially harder to follow when you don't know which part of the twenty-piece jigsaw you're on.
(In case you were wondering what this was all about, the C#letters are tiny molecules in your bloodstream that eventually assemble themselves into the molecular equivalent of an awl, and then they go punch holes in bacteria. It's wonderful.)
Meanwhile, C4b2b cleaves C3!
C3b joins C4b2b to be C4b2b3b...did we mention C5 yet? Well, OBVIOUSLY C4b2b3b cleaves C5, and now we have C5b, which clearly shows why the answer to the other question was C5b, C6, C7, C8, and C9. And since this was the classical pathway, that's why you were wrong. The alternative pathway uses C3bBb. That's a B, not a 2. (sheesh, get it right)
But I was a silly student and didn't realize that we were supposed to know the alphabet in this new, convoluted form. I just had it summarized in my notes as "Legos."
Probably it would help if our prof used something other than the detailed diagrams from our textbooks. Lecture becomes exponentially harder to follow when you don't know which part of the twenty-piece jigsaw you're on.
(In case you were wondering what this was all about, the C#letters are tiny molecules in your bloodstream that eventually assemble themselves into the molecular equivalent of an awl, and then they go punch holes in bacteria. It's wonderful.)
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