Name Game Anatomy Answers

Last week, I posted a question:

In the following list of words (lettered A-H because supposedly we get up
to 7-13 answer choices on the USMLE) try and guess which word is NOT a name
for something found in the adult human body (I'll do an embryo quiz later):
A. Olive
B. Lumbricals
C. Pyramid
D. Chordae Tendinae
E. Kasseri
F. Pylorus
G. Supinator
H. Gastrocnemius

I suspect that some of you might have thought the answer was olive or perhaps pyramid, but you'd be wrong. Now, I know that those aren't really fair as there are olives outside the body and there are pyramids outside the body, but they are also found in the body.

A: The olives are found in the brain stem. There are superior and inferior olives. The superior olivary nucleus is involved in hearing and the inferior olivary nucleus is involved in transmitting information to the cerebellum. The cerebellum helps your brain coordinate movements (like walking in a straight line or touching your hand to your nose with your eyes closed).

B: The lumbricales are little muscles in your hand that help the fingers abduct and adduct. To abduct your fingers is to spread them out and to adduct is to push them together.

C: The decussation for the pyramids are the part of the lower medulla (part of the brain stem) where approximately 80-90% of the corticospinal tract fibers cross sides of the body. Basically, this meas that the primary motor cortex in the cerebral cortex sends down a signal for something to move (this is voluntary movement of skeletal muscle). This signal travels down the brain, but when it reaches the brain stem (lower medulla), the signals from the right side of your brain cross over to the left side of your brain stem and continue to travel down the left side of the spinal cord to control muscles on the left side of your body. Obviously, this happens on both sides of the body. This is one of the reasons why people have contralateral (opposite side of the body) problems after having a stroke. Also bear in mind, different spinal tracts that carry different information (like tracts that go up the body with sensations of pain, vibration, pressure, and proprioception) cross at different places and some things even cross twice in the brain. I have the upmost respect for anyone who can be a neurologist because I think it is incredibly, incredibly difficult and I really don't know much since I'm only in medical school.

D: The chordae tendinae are found in the heart. I think they might be my favorite part of cardiac anatomy. They are cord like projections (Farley says they look like floss) that are found on the mitral and tricuspid valves, which attach to papillary muscles. In other words, the chordae tendinae help close the mitral and tricuspid valves and prevent regurgitation of blood (basically, you want blood to flow in one direction and the chordae tendinae help the valves close so that blood can flow backwards).

E: Ah, the answer to the question is E! Kasseri is a Greek cheese of medium consistency made with unpasteurized goat's milk. From what I've read, it has to be unpasteurized because that ensures the correct flavor of the cheese. Kasseri is suppose to be similar in texture to Parmesan, but not as creamy. I've never thought of Parmesan as creamy, but I guess I'm just not an expert on cheese.

F: The pyloris is bottom part of the stomach that leads into the small intestine. It has different cells which secrete acid and enzymes to breakdown food. It is also very famous (at least amongst medical students) for pyloric stenosis, which is when newborn babies have projectile vomit. Pyloric stenosis is when the connect between the stomach and the small intestine is too tight and the little baby cannot keep food down and they are always hungry. Apparently, the term projectile vomit is very serious as babies with this problem have been known to send vomit several feet across the room! Babies are usually diagnosed at about three weeks old (although it can be up to about 5 months old). I can't imagine a three week old causing such a mess!

G: The supinator is my favorite muscle in the upper arm because the name tells you the function: it supinates! To supinate the arm is to bring the arm and hand into a supine position. Or you can think of it as twisting, like to open a bottle of wine.

H. The gastrocnemius makes up the majority of the calves. It is the biggest muscle in the calve and is involved in helping us stand and walk. It also contracts and looks shapely when one wears high heals. It sometimes can cause involuntary, painful contractions (charlie horse)--I had one a couple weeks ago when I didn't stretch well after working out.

So that is the end of the first Name Game. I'll post another couple in the next few weeks. I hope you got the answer correct and that I was able to tell you something new and interesting about the anatomy!