what we need in this city are more osteoblasts…

and fewer osteoclasts…

said the cell biologist who lectured today, right after he described osteocytes interconnected via canaliculae as “an enormous network, kind of like facebook for the skeletal system.”  That’s right Dr. Levine, you know who you’re talking to…this one right here in the back row because she slipped in a few minutes late.  In all seriousness, I do appreciate that you use terms I understand to explain what I don’t–you’re like a gentler, more PC version of Dr. Gregory House.

It occurred to me that I haven’t written all that much about what I’ve been learning in med school so far.  I know today was only day eight of class, but I already feel like I’ve absorbed a ton…not enough, but a lot.  (God, I’m sure the rate is only going to increase.)  Anyway, MS1s start out in four main science-y classes in Mod 1 (essentially first semester): metabolism (biochem); genetics; cell biology (histology); embryology.  We also take a class on Doctoring, but it extends throughout the four years and, to my knowledge, does not include multiple-choice exams.  In mid-September, we’ll take finals in genetics, cell biology, and embryology, pick up three new classes, and continue with metabolism for another month.  Frankly, I’m going week to week (day to day) at this point, so I’m not sure what comes next–don’t think I don’t notice that I’m doing exactly what used to (continues to) frustrate me about how John deals with his work schedule.  Sorry honey.

Today’s lecture in cell bio was on bone and cartilage.  So far, it’s the same general material that we learned in Bio 101, but with more detail and explanation…like, I somehow don’t think the mnemonic “osteoBLASTS build (bone), osteoCLASTS crush (bone)” is going to get me through the related questions on the exam.  Still, that’s what Dr. Levine was getting at when he made the comment that what Philly needs are more osteoblasts.  He was commenting on the fact the roads are somehow always under construction, and that the workers who build the asphalt back up just cannot keep up with those who tear it apart, so we’re always left with weak rubble being reabsorbed into circulation (the commuters being the blood cells and plasma in this analogy).  Having busted my butt on the torn-up Chestnut Street for the last several days, I couldn’t agree more; we need more osteoblasts.

The process of bone remodeling is still pretty mind-boggling to me.  I think of bone as such a permanent, stable thing…but the truth is that my skeleton is likely 100% different, on a cellular level, than it was a decade ago.  Even crazier, in the first year of life, almost 100% of the skeleton is replaced–in one measly year!  Okay, this might not seem too terribly exciting, I just get a kick thinking of all the ways in which my body is doing work, maintaining a dynamic equilibrium, building something (in this case bone) and tearing it apart based on what is needed in the blood–makes me feel a little better for opting out of a run today.