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Taste buds that sense different molecules are distributed unevenly across the tongue resulting in regions that most strongly perceive one taste modality. This regionalization is the reason wine experts insist that using different glasses affects the taste of the wine; the liquid is channeled toward a particular part of the tongue. In the 1980’s, scientists identified diffuse glutamate and ribonucleotide receptors that legitimate countless claims by chefs over the last 200 years that umami or “savory deliciousness” is a basic taste. These receptors respond most strongly to salts of glutamic acid, such as monosodium glutamate (MSG). Umami overlaps, rather than excludes, the other flavors and tends to modify one’s perception of them. Interestingly, these same receptors continue down the throat and into the stomach where their signals to the limbic system (emotion processing area of the brain) continue to influence the sub-conscious opinion of a meal’s palatability as it is being digested.

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 A nerve cell’s axon is the long, thin portion that resembles a wire, both in form and function. A human axon is typically 1 µm in diameter. While most higher animals responded to selective pressure for faster nerve conduction by insulating their axons, the squid evolved freakishly large wiring. Squid have a single giant axon up to 1 mm in diameter (1000x the size of a human’s) that carries the panic signal from the brain to their water siphon escape mechanism. This nerve is so large that scientist Andrew Huxley was able to insert an electrode into the cell’s interior and perform experiments that ultimately provided the biochemical explanation for how nerves move information from place to place. These experiments essentially founded the discipline of neuroscience and won him a shared Nobel Prize in 1963. The previous year, Watson and Crick received their Nobel for founding the discipline of genetics and, the following year, Bloch and Lynen received the prize for making people feel bad about what they eat for the first time. What an age to be alive.

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The characteristic lub-DUB sound of a heartbeat is caused by turbulent blood flow associated with the closing of heart valves. The first sound is the overlapping closure of the tricuspid and mitral valves while the second sound is the aortic and pulmonary valves. Taking a deep breath and holding it increases the pressure in the pulmonary circulation enough to delay the closure of the pulmonary valve a fraction of a second. This delay is enough to split the second heart sound into distinguishable parts.

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Enzymes accelerate the speed of chemical reactions by reducing the energy required to start the reaction.  Red blood cells are full of carbonic anhydrase, and enzyme that helps carbon dioxide in water transition from an unstable dissolved gas to the more stable carbonic acid and back again. Carbonic anhydrase is the fastest known enzyme with a single molecule catalyzing up to 600,000 reactions / second. Since the creation of carbonic acid changes the pH of the liquid, carbonic anhydrase is also involved in controlling the acidity of bodily secretions, including saliva. Incidental secretion of carbonic anhydrase into the saliva is the reason that carbonated drinks fizz a great deal more in the mouth than they do in a cup.

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There is a sense in which things in the stomach or intestines are not “inside” the body. Compare a set of dentures to a lip piercing and it becomes evident that only the latter has passed into the closed body cavity. With that in mind, consider that the digestive organs are constantly secreting water, salts, and chemicals “outside” the body with the expectation that they will be recovered in the lower intestines. These secretions total about 7 L/day and are 98% reabsorbed. In contrast, an adult male’s total blood volume is only about 4.5 L. Similar proportions exist for salts and cholesterol. In essence, the digestive system works by “juggling” vital resources into a space that contains any old thing you decide to swallow. It is no surprise that a bout of vomiting/diarrhea quickly leads to dehydration and electrolyte imbalances.

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The autonomic nervous system, which takes care of involuntary responses, is divided into two parts: the sympathetic (generally excitatory, “fight or flight) and the parasympathetic (generally calming, “rest and digest”). In virtually every case, the parasympathetic system uses the neurotransmitter acetycholine (Ach) to exert its effects while the sympathetic system uses epinephrine (adrenaline) or norepinephrine. Most organs have receptors for both chemicals on them and speed up or slow down depending on what signal they get. The notable exceptions are sweat glands and the tiny muscles that cause goosebumps. These are wired to the sympathetic nerves using Ach-based connections. This is why a sudden fright (sympathetic stimulation of the adrenal glands leading to systemic release of epinephrine) causes dry skin but a slow, lingering threat (sympathetic stimulation of all organs via nerve-tissue connections) causes profuse sweating and goosebumps. While raising the hairs on the skin makes sense as part of a stress response in furred mammals, the reason for this unusual wiring to the sweat glands remains a mystery.

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Eyes Propped Open

Imagine that a friend comes to visit you from a foreign country and tells you about a drug that is common in his town. He says almost everyone uses it to feel more energetic and happy. It’s completely legal, and consumed in shops, bars, offices and homes, even by children. He says he takes it himself and doesn’t feel right without it. In fact, the one time in recent memory that he didn’t have any for a while, he was so tired and unpleasant to be around that other people noticed. What is your opinion of this practice? Is it healthy? Responsible? Safe?

What if I told you he was talking about caffeine and that “a foreign country” meant “not a foreign country at all”? Likely, your opinion has suddenly changed, if only because your personal experience fills in some of the unknowns and assures you that it’s not that bad. And you’re right, the dangers of caffeine are minimal, that’s why it’s legal here, but the fact remains that your friend is addicted to something and thinks it’s part of what makes life “normal” for him.

I understand that there are people with chronic medical conditions or intractable pain that are dependent on certain drugs to be functional. I also understand that occasional recreational drug use can be part of a healthy lifestyle. However, I do not agree with an immoderate normalization of an exogenous substance into a person’s daily routine. For example, if you tell me that you take antacids two or three times a day to treat heartburn, my first question is: why do you have such bad heartburn all the time? Similarly, if you take caffeine every day to “treat” fatigue and irritability, it seems reasonable to investigate why you feel that way so often.

For healthy people who use caffeine every day, a significant part of the reason is withdrawal.  In fact, some researchers believe that the majority of caffeine’s appealing physiological effects are the direct result of reversing its own withdrawal symptoms. Furthermore, its central nervous system activity as an adenosine receptor antagonist can lead to subtle disruptions of the normal sleep cycle and a corresponding increase in early-morning fatigue. However, it is just as important to figure out whether caffeine use is a “self-medication” for something like sleep apnea, clinical depression, or an unhealthy lifestyle that precludes adequate sleep.

My close friends that have followed my recent experiences with removing caffeine from my routine may be quick to brand these ramblings as the overzealous rant of an ex-addict. I want to assure my readership that my thesis is less about purity and more about self-awareness. Our daily habits are what allow us to focus on getting through a stressful day, but don’t for a moment believe that an overall success at life automatically justifies each individual behavior.

Take a minute to make a list of things that you “can’t live without” (exclude people, animals, or prescription drugs). Now ask yourself what you get out of using/doing that thing. What are the costs? Have you ever felt like the thing should be less important to you? Is there any chance that the item is on the list because it helps to compensate for something else that shouldn’t be going on? Does someone else make a profit off of your involvement with this thing? Do you have a backup plan if this thing is ever unavailable?

Hopefully, your habits still look healthy and reasonable. If not, there’s no day like today.

Homeless Healthcare

Poverty is a complex syndrome of interlocking problems. A lack of financial and social resources often goes hand in hand with poor education, poor health, and a tendency toward criminal activity. When we interviewed S., we heard the story of a woman who got pregnant at twelve years old and dropped out of school after the seventh grade. She had four more children by different partners and was physically abused by at least one of those men. After a prison term and an attempt at rehabilitation, she found that all she was qualified to do was the most basic of food service work. Unable to afford an apartment with inconsistent work and several children, she was essentially homeless, drifting from friend to friend until she ended up in a church-run shelter.

S. has made some very poor choices in life. Although she is highly motivated to improve her situation, she still needs substantial help and guidance to form and execute a workable plan. The problem is not so much that she is weighed down by the consequences of her past, but that her ability to make good choices is severely impaired and probably always has been. The shelter gives her food and lodging while a social worker gives her small goals to accomplish each day. Little by little, she learns how to think like someone who has the skills to take care of themselves. S. has a long way to go.

Her health suffers in the meantime. In one breath, she told us that she had no difficulty getting health care and that Medicaid covers all of her needs. In the next, she described long-term, debilitating tooth pain and ER visits for chronic conditions. She said that when she does not have the time to go to a doctor or cannot find anyone who takes Medicaid, she “just deals with it.” This progressive normalization of her health has left her unable to eat anything but very soft foods.

It is not too late for S., but the amount of effort required to get her back on her feet will be enormous, and even then, her prospects are grim. Studies show that the homeless population has a significantly shorter life expectancy and increased morbidity from chronic conditions when compared with the rest of society (Hwang et al, 2009, Wiersma et al, 2009). Emotional and logistical problems stand in the way of homeless people seeking care or sticking to complex treatment regimens (Montauk, 2006). Self destructive behaviors and low health literacy can exacerbate, or even cause, disease at rates far in excess of their housed counterparts (Wiersma et al, 2009).

If any part of our conversation with S. can be crystallized into clinical advice, it is that a homeless person’s self assessment of their abilities cannot be trusted. Poor health literacy and denial contribute to a misestimation of what therapies are feasible. Even a very qualified person is still at the whim of the inherently unpredictable nature of an itinerant lifestyle.

Social and physical problems impair an individual’s ability to achieve self-sufficiency and often stunt the development of the next generation (Reynolds et al, 2007). While the clinical practices summarized by Montauk should be helpful for treating the existing population, the better solution is always prevention. Early childhood intervention programs, such as the Promise Neighborhoods Initiative, Harlem Children’s Zone, or even the Perry and Abecedarian Preschool Programs from the sixties, reach children while their minds are at their most plastic. Children ages three to five in at-risk environments are taught critical life skills and barriers to their development are removed to the best of the program’s ability. Education is cumulative, so early deficits can be difficult to recover form. Long-term data from the early programs shows significant improvements in job skills and quality of life of those children who participated (Reynolds et al, 2007). Early skills learning not only increases motivation, it also makes later education more efficient and more successful (Knudsen et al, 2006). Furthermore, early childhood programs show a very positive cost-benefit profile even before intergenerational effects are taken into account (Reynolds et al, 2007). The Knudsen et al study demonstrated that

In contrast to the documentation of significant long-term effects from model preschool interventions, later remediation efforts have been shown to be considerably less effective. School-age remedial programs for children and youth with cognitive limitations, for example, generally have had a poor record of success. Similarly, public job training programs, adult literacy services, prisoner rehabilitation programs, and education programs for disadvantaged adults have yielded low economic returns, with the returns for males often being negative.

Although the effects are very long-term, it seems obvious that early childhood interventions should be an integral part of any serious plan to address the causes and conditions of homelessness.

While we spoke with S., her ten month old son nursed a bottle and drifted off to sleep. He stays with her in the shelters and waits for her while she looks for work. He is too young to know it, but he is a constant reminder that the consequences of their lifestyle are very real and threatening. She has every reason to make things better for her family, she just doesn’t know how. Even though our academic preconceptions turned out to be largely correct, they did not include the human perspective on the struggle against poverty. It takes a detailed understanding of a homeless person’s unique circumstances to design treatments and interventions that have any effect at all. In the end, poverty is about more than money and solutions will take more than spare change.

Culture

This is an excerpt from a class assignment. In preparation for an upcoming project centered around interviewing some of the local homeless population, we were asked to reflect on “our experience with cross-cultural communication” and our “expectations and concerns regarding [the interview].” Some meta-commentary follows the essay.

“Culture” is a funny word. Its Latin roots center around the idea of tilling the land and actively inhabiting a place to make it yours. Change the concept from “me” to “us” and from agrarian to urban, and it becomes less about marking the boundaries of your farm and more about drawing the hazy lines that distinguish “us” from “them.”  To complicate matters, the sets of behaviors that define a culture are not mutually exclusive and, especially in America, an individual belongs to more than one culture at a time. A person is a complex product of disparate influences.  While generalizations about national, gender, or corporate identity are sometimes useful, using a “cross-cultural” communication model tends to emphasize the exact problems that are hindering communication. In almost every single case, the similarities between two random people far outweigh the differences and serve as a much stronger foundation on which to establish rapport.

As a unique person, I have to reach across “barriers” every time I interact with anybody else at all. No one else lives inside my head and has my same experience of the world. With friends, I have the luxury of shared ideas and memories, but with strangers I have to look a little harder. I pulled a splinter from a man’s finger in a Mexican border town a few years ago and, though my Spanish is poor, I found that a little trust and wanting the same thing was good enough communication to get the job done. If I’m so uncreative that I can’t find anything in common with the person I’m talking to, I should remember that I share gender with a little less than half the world and humanity with all the rest.

I expect that a casual conversation with my dispossessed neighbors will be relatively straightforward. I have no doubt that somebody somewhere will be eager to share their story. I am a little bit concerned that I might fall into the trap of being judgmental about people’s life choices. Perhaps I should remember the words of an old mentor: “Everyone does the best they can with the tools they have. “

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With a few days perspective, the ideas expressed in this essay seem like naive platitudes. I think I was more concerned with rebelliously challenging the presuppositions of the prompt than exploring my own experience. I definitely got caught up in my own lyrical writing style and may have composed something that was more form than substance. I generally feel that I’m pretty good at talking to people and concealing, if not suppressing, my judgments. It isn’t because I expect the worst from people, just that I feel like I can accept and roll with anything that comes up.

The actual interview, which was conducted last week, was performed in the immediate presence of another mother’s two-year old child that screamed at the top of his lungs for 45 minutes straight. It completely wiped any useful thoughts from my head. Thankfully, this was a group project.

A paper based on this interview will be posted tomorrow.

Hydrogen peroxide (H2O2) is used to clean wounds but it’s also a poisonous waste product of normal metabolism. Almost all human tissues have an enzyme called catalase that breaks hydrogen peroxide into water and oxygen gas. When you put this liquid on a wound, the catalase reaction occurs on the surface of your own cells and the resulting foam lifts germs and debris away from the tissue. Since most bacteria have a catalase of their own, H2O2 makes a poor antiseptic. Always flush the wound with clean water before the foaming stops or everything you’re trying to get rid of will settle right back down onto the healthy cells.

Ethanol (grain alcohol) is also a metabolic waste product. Anaerobic microorganisms (including brewers’ yeast) that cannot “burn” sugar harvest some of the high energy bonds in a 6 carbon glucose molecule by cutting it into 3 chains of 2 carbons each and excreting them as waste. We evolved a mechanism to break down ethanol because we have anaerobic bacteria in our intestines that produce a small amount of alcohol every day. Because it is designed to handle only this small amount, our detoxifying machinery is easily overwhelmed by even a single beer.

The cells of plants, animals, and fungi generate energy using many self-contained organelles called mitochondria (#9). Plants also use chloroplasts which are similar structures that allow them to capture sunlight. The construction and maintenance of every other part of the cell, from the walls, to the scaffolding, to the tiniest machinery is coded for and directed by the DNA in the nucleus of the cell. Mitochondria and chloroplasts however, appear to have their own DNA, make their own proteins, and replicate independently of the rest of the cell. Most biologists now subscribe to the endosymbiotic theory that describes these structures as the descendents of bacteria that our single-celled ancestors attempted to eat about 1.5 billion years ago but could not digest. They’ve been with us ever since.

Red blood cells get their color from the iron-containing pigment heme. Genetic defects in the heme synthesis pathway, called porphyrias, result in a wide variety of serious physical symptoms. One defect in particular, uroporphyrinogen cosynthase III deficiency, produces red urine, a red pigment in the teeth, facial disfiguration, excessive hair growth, extreme sun sensitivity, and iron deficiency. Some historians believe this rare condition is the origin of the vampire myth.

Fat is stored in specialized tissue as the long-chain hydrocarbon palmitate attached to a glycerol scaffold. Palmitate is metabolized into water and carbon dioxide. Someone who is in the process of losing weight is getting rid of the mass by urinating more frequently and exhaling slightly heavier breath than normal.

When a person does not ingest any carbohydrates (starches and sugars) for an extended period of time, the body begins to burn fat. The brain is not very flexible in terms of its fuel requirements and is heavily dependent on sugar for proper functioning. It will grudgingly switch over to using ketobodies (an intermediate product of fat metabolism) but it doesn’t work quite as well in that state. Some people report a feeling of euphoria, while others say they have very vivid dreams or simply that they can’t think clearly. Ketosis may be the reason that prolonged fasting is associated with spiritual renewal.

Cells use motor proteins like dynein and kinesin to transport materials from one side of the cell to the other. Molecules to be moved are packaged into bubble-like vesicles, bound to a motor protein, and sent along one of the cell’s main structural highways. Dynein and kinesin are shaped like platforms with two small legs on them that allow the vesicles to be “walked” wherever they need to go. In the extreme case of sensory neurons in the leg, this journey can be more than 3 feet long.

The Asshole Factory

My first semester is officially over. Medical school is 4 years, and an ER residency is another 3, so this milestone puts me 1/14 of the way to being a fully licensed physician! Settling into a med student’s mindset has been as much about letting go of my past concerns as it has been about looking to the future. Bad grades in college, professional failures, and fears that I wasn’t achieving my potential in life are no longer relevant. However, the worry that medical education is going to change me into a big fat jerk still lingers in the indecisive limbo of my subconscious.

Prior to admission here, I encountered an abnormally high percentage of asshole doctors. Specifically, I’m describing a personality that carries with it a sense of paternalism, entitlement, and false urgency. While not universal, and perhaps not even the norm, the stereotype exists for a reason. The only logical explanation seemed to be either that the med school establishment was recruiting people like this or that it was creating them.

So far, I’ve found this trait to be rare among my classmates. Specific cases can often be explained by youthful naiveté or excessive parental support rather than inherent social pathology. Furthermore, the class culture seems to be one of teamwork and support. I have heard legends of other schools that grade on a curve, where one’s ability to do well depends directly on everyone else not doing well, and students take pains to sabotage their fellows. I think such an atmosphere is counterproductive and entirely unlike the real world. Yes, I’ll be measured against my peers in the hospital, but it’s my ability to understand and use the talents of the people on my team that will produce better results than those who feel like they’re superior to their peers and their patients.

In the end, there may prove to be a lingering academic threat capable of distorting my personality but that chances of that are seeming less and less likely. All signs are pointing to me being in the right place at the right time in my life and that I’ll still be the same person all the way through.

Silly Name Parade

Back in the 70’s, three American scientists were experimenting with the embryological development of fruit flies. They found that certain proteins were concentrated in certain areas of the body and that that unevenness provided individual cells with information about where they were in the body and what kinds of tissue they should become. A mutant fly embryo that lacked one or more of these proteins was improperly segmented and exhibited small protrusions from the surface that made it resemble a tiny hedgehog. The term “hedgehog protein” seemed like a good descriptor at the time and, as individual proteins were discovered, the scientists arbitrarily named them after actual species of hedgehog. After a decade of doing this research, they named one of their many new proteins “Sonic Hedgehog” in reference to the Sega video game mascot. Guess which one turned out to be incredibly important in human development and earned the scientists a Nobel Prize in 1995.

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In 1975, a British biologist named Dr. Edwin Southern invented a method of separating DNA fragments via gel electrophoresis, nitrocellulose blotting, and probe hybridization. His colleagues named this technique “Southern blotting” after him. A similar method for RNA was soon pioneered and named “Northern blotting” because, again, it just seemed like a good idea at the time. Not wanting to break with what was a apparently a tradition, another group called their protein separation method “Western blotting” and paved the way for the subsequent introduction of a protein-DNA hybrid method termed “Southwestern blotting.”

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The human genome codes for some 140,000 proteins and each one needs a name. The sensible thing would be to give them catalog designations in a large database, but human language abhors the presence of impronouncable, alphanumerical gibberish. Somewhat descriptive names (Growth factor receptor-bound protein #2) are quickly condensed to initialisms (Grb-2) and then re-expanded into something that can be mentioned at the world’s most boring cocktail party (“Grab2”).  Here, English has somehow rediscovered one of the big problems with the old languages: there aren’t enough vowels to go around. Is Grb spoken as “Grab” or “Garb” or “Grub” or “Greb?” That last one is less likely, as we prefer to use real words whenever possible, and it’s precisely that tendency that makes the enzyme Methylenetetrahydrofolate reductase (MTHFR) all the more hilarious.

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In biochemistry, a “kinase” is an enzyme that adds a high energy phosphate group to another molecule. Much of the cellular machinery uses these phosphogroups as a means to activate or inactivate certain enzymes. A single kinase enzyme, activated by an external cellular event, can activate many of its target molecule, including different downstream kinases, thereby exponentially amplifying the effect of the initial stimulus. A particular effector protein, MAP, is phosphorylated by MAP-kinase which is, in turn, phosphorylated by MAP-kinase-kinase. But what activated that, you ask? Why MAP-kinase-kinase-kinase, of course.

OSCE, SCHMOSCE

A couple of weeks ago, I completed my first Observed Structured Clinical Exam (OSCE, “AW-skee”) as part of the continuing adventure that is medical school. An OSCE is a skills test in which you step into a small room with a “standardized patient,” i.e. a stranger who has memorized a script, and conduct your exam while the faculty watches through a camera. This particular test covered the art of taking a patient history and sought to determine if I could capture all of the relevant parts of a patient’s story via a relaxed and efficient interview. I failed it.

There are several complicating factors that make this process much more difficult that it sounds. The biggest problem is that there is no standard set of questions that gets you “all the answers.” I have to approach the gathering of information as one who cannot distinguish between things that are relevant to the patient’s condition and those that are not. My patient presented with stomach problems and the interview had to drift through topics such as her use of illegal drugs and her sexual history.  Those facts might have bearing on the case or they might be a rapport-damaging waste of time. Clinical ignorance is the only acceptable approach for a student to take.

Even if I did have all the perspective of experience, patients often do not file the facts about their lives into the same categories as I do. They simply might not think of C-sections as surgeries or St. John’s Wort as a medication. Consequently, I basically have to ask everything multiple times: “Are you treating your condition with anything? Are you taking any other medications? How about herbals or over the counter pills?” Even then, a patient might forget or withhold something and the failure to document it is still mine.

Similarly, it’s also important to remember what you actually asked. For example, negative responses to “Have you ever been diagnosed with a psychiatric disorder? Do you have any anxiety or depression?” should be written up as “Patient denies depression, anxiety, or other psychiatric disorder.” This specificity both prevents poor clinical assumptions and reduces my liability a little, but It’s still a challenge to reproduce this entire conversation from notes.

I am confident that I passed the exam retake and the irritation I felt from barely failing a test because of a flawed grading structure is fading. I’ll just use this as the learning experience it was meant to be. The hospital environment will not be as forgiving.

Bonus Post – Fun Anatomy Facts

Eye Muscles

Movement of the eyeball is a coordinated effort of six muscles. The superior oblique muscle (number 7 in the image) originates from behind the eye but pulls on the eyeball from in front of its central axis of rotation. It is mechanically able to do this because it is strung through a tiny pulley mounted on the upper-medial aspect of the orbit.

Tendon in wrist
The Palmaris Longus muscle runs from the forearm to the palm of the hand (tendon pictured here). It is an evolutionary leftover of a muscle used to extend claws and is missing in about 20% of the population.


The nasal cavity contains three wing-shaped bones on each side called the turbinate conchae. They are covered in a well vascularized mucous membrane that both warms and moistens the air passing over them. Their unusual shape also imparts some spin to the air that is strong enough to centrifuge out dust and debris, throwing it against the wet walls.

Arm Vessels
Most arteries and veins are designed like tree roots with a large vessel branching into progressively smaller divisions. The blood vessels of both the arm and the leg have numerous points of anastomosis or places where small vessels branch off of a larger one only to loop back and reattach later. This is because flexing and moving the limbs routinely pinches off the blood supply and forces it to be rerouted through these alternate pathways.

Brachial Plexus

Almost all of the nerves in the arm originate from a large nerve bundle called the brachial plexus located in the armpit. Here is a simplified version of this structure. The anatomical vulnerability of the brachial plexus is the reason we have acquired a strong, defensive, anti-tickle reflex in that area.

Testicular Vessels
The ovaries and testes initially form in the middle of the abdomen as a fetus develops and take their blood supply with them as they migrate. Consequently, the gonadal arteries and veins (labeled here as “internal spermatic vessels”) originate from a point about level with the bottom of the rib cage and travel 6-8 inches to their destination.

Middle Ear

Most of the muscles used for chewing are controlled by one nerve (mandibular branch of trigeminal nerve, CN V-3) that originates directly from the brain. Fibers from that same nerve also supply the tensor tympani: a tiny muscle that tightens the eardrum to dampen the sounds of eating.

Catching Up

The last few weeks have been somewhat of a blur. Since we were last together, anatomy has come to an explosive conclusion and I have already completed one test for the next block. While anatomy was a harrowing journey through an impossible knowledge set, I still think back fondly on some of its highlights.

Attending the pre-lab lecture, in which they described the upcoming day’s dissection procedure, was a lot like watching a cooking show: it was entertaining, inspirational, and fantastically misleading. Just as Julia Child can whip up a two hour roast in a single thirty minute time slot, we discovered that simply cutting open a skull to pop out the delicious insides was a 45 minute job requiring three people and a great deal of swearing. Similarly, the pre-labs did not and could not cover the dazzling range of variant structures. Looking for the left renal artery? Surprise! There are two of them today. Can’t find the hepatic portal vein? It’s traveling through the middle of a tumor.

In all fairness, the disparity between book-learning and reality will be even more pronounced later on in my practice. I think the skill that anatomy was really trying to teach was how to deal with variation and frustration. We learned how to identify things based on what’s around them and to use landmarks to trace the unfamiliar back to the familiar where it could no longer hide from us. That should come in very handy, even as the fine details start to escape me.

Our current block, Biology of Cells and Tissues, is an “integrated” conglomeration of cell biology, genetics, histology, and biochemistry. The core elements of this class are pretty easy but, like Anatomy, there is also a hidden skill that they are asking us to learn. I’ve been learning these sciences separately over the years and now it’s time to bring them together to make them part of a unified understanding. Should be fun.