Human Anatomy at Colby

Alexandria Lucas: Meeting with High School Anatomy Students

February 24th, 2015 · Comments Off on Alexandria Lucas: Meeting with High School Anatomy Students

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In high school, I never had an opportunity similar to this one in which I was able to visit a college science class and interact so directly with the college students and the material they are learning. Not only did they get to come and visit, but they were able to dissect a pig’s heart and we were there to help them do it! I do not know what have been a cooler fieldtrip in high school than this one.

It was very interesting and engaging because as we walked around and took them through the lab exam we had just taken, they could identify some of the anatomy and share knowledge about things we may not have learned because they too were currently in an anatomy class. In addition, it was helpful to be in the teaching role as we described and identified the anatomy on the different models. I think this truly works as a way to understand and learn the material better, and is not often a position that us college students are in. This particular lab test was on the heart, eye, ear, and the brain.

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After taking them around our lab exam, we went downstairs to dissect the pigs’ hearts. Each group had their own heart to dissect, and it was both an opportunity for the students to learn about some of the anatomy we had just reviewed as well as to explore whatever pieces of the heart they found intriguing further. Some groups dove right into ripping apart the heart, while others took more reserved action and precise cutting to open the heart.

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The purpose of this field trip was initially supposed to be meeting with the students to help them come up with ideas for the Maine Math and Science Alliance Science Fair. Because of our current class, we brainstormed ideas that directly related to anatomy and physiology, such as do different styles of music have an effect on the heart rate, or do different color filters of light effect pupil dilation in similar or varying ways.

Perhaps my favorite part of the day, which was the only unplanned part as it happened, was answering questions the group of students I was showing around had on college science classes, premed requirements, college class schedules, and more. Before I came to Colby, I truly had no idea what college was like, and needless to say I also had no idea how classes, lectures, exams, etc. operated. They were very curious about what a typical day looks like and what is different about high school classes versus college classes, and the two biggest things I shared were that exams make up very large portion of your grade particularly in science class, for very infrequently do you have daily homework assignments that significantly contribute to your grade like in high school. I also shared the much greater need for independent learning and studying in college, for it is your responsibility to make sure you understand the material covered in class during lecture and to study outside of class if you don’t. It was fun to be able to reflect on the time I have had here at Colby so far and share my learning and knowledge with students who will soon be headed off to college themselves.

Tags: Bi265j · Special Activities

Laurel Edington: MMSA Mentoring Session

February 24th, 2015 · Comments Off on Laurel Edington: MMSA Mentoring Session

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One of my favorite parts of this month was mentoring high school students involved in the Maine Math and Science Alliance. Each grand rounds group was paired with two high school students. The two girls my group worked with were named Shea-Lynn and Cierra. Shea is a home-schooled junior and Cierra is a sophomore at Dover-Foxcroft. The plan for the day was to show them around the lab, talk to them about anatomy and physiology, and help them come up with ideas for a science fair project.

Before the students arrived, we took our second lab practical and then walked around talking about the answers to the exam so that we could show the high school students what we have been learning over the past week.

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IMG_5584            When they arrived and we were in our groups, we went through the entire exam with them. We all looked at the models and slides, explained the answers to each question, and explained the functions of each anatomical structure. This was great because it reinforced the material. Over the past few days I had been trying to memorize all of the structures of the neurons/spinal cord/brain, eyes and ears, and the cardiovascular system. By explaining the structures and functions to Shea and Cierra, it helped me to learn and understand the material even more.

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After the lab tour, each group dissected another pig heart since there were some hearts left over from the week before. I was really excited that I was able to be involved in a dissection on this day because I wasn’t able to be in class when we did the dissections the week before. Shea and Cierra, although a little timid at first, dove right in and were able to find the aortic and pulmonary valves very quickly. They did the of the dissection while we instructed and did a little demonstrating.

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The last part of the day (after a quick lunch break) was used to help the students come up with topics for science fair projects based on anatomy and physiology. Cierra’s family owns a farm with over 50 beef cows so she wanted to do a project based on livestock. Together, we all came up with the idea of seeing how different types of food affect the growth of the cows. If she did this project, she was thinking of finding the mass and other size measurements for the cows of different ages and comparing the measurements between the cows that were fed hay and the cows that were fed grain. Shea was interested in determining if different emotions caused changes in blood pressure and heart rate. We talked about having people watch different videos that would cause them to experience different emotions and then she would take heart rate and blood pressure measurements before and after the videos to detect any changes. This day was very rewarding because we were able to reinforce what we have been learning, help high school students become excited about science, and we were able to have a great time.

 

 

Tags: MMSA Mentoring Session · Special Activities

Ivan Yang: My experience in A&P

February 24th, 2015 · Comments Off on Ivan Yang: My experience in A&P

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Even though I am a molecular biology major, I had not taken any biology courses in the fall semester, so my advisor highly recommended me to take a biology course for JanPlan. After checking the course listings for January, I decided on a whim to sign up for the Intro to Human Anatomy and Physiology course. Later that week, I met someone who had taken the course last January. She informed me that if I was to take BI265, I would have to be prepared to learn a lot in a small amount of time. There was a wealth of interesting knowledge to be gained from the course, but, she warned, if I was expecting to cruise through JanPlan, I should drop the course. Not sure if I should take her seriously or not, I laughed it off and didn’t think about her words much after that.

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After the first week, I definitely knew that this class was not to be taken lightly. The first week was especially rough because of the flipped lecture setting. Not only did we have to study for daily quizzes and lab exams, but also we had to listen to lecture and lab podcasts for the following day’s lecture and lab sessions. I was completely unprepared, and I was forced to adjust my mentality, my study schedule, and my lifestyle habits. However, while there was a seemingly surreal amount of work involved in the course, the amount of material that I absorbed during the four weeks of JanPlan truly astounded me. In addition, after putting in maximal effort just to learn the basics of human anatomy and physiology, I gained deep respect and admiration for the structure and workings of the human body. I truly came to enjoy the class and the subject, and soon enough I found myself embracing Dr. K’s recommended healthy lifestyle habits.

Beyond learning material through lectures and labs and finding a healthy lifestyle balance between working and resting, I also had many opportunities to do things that I had never done before. For example, for the first time in my life, I had the opportunity to perform a wet dissection of a pig heart. Although I was confused at first due to initial difficulties in matching the neatly-drawn heart schematics in my mind with the real deal in my hands, I thoroughly enjoyed the experience of opening the heart with my own hands, placing my fingers through the valves and blood vessels to see where they connected, and seeing how the real tissues and membranes of the heart correlated with the models in our anatomy lab. In fact, I’m sure I would have enjoyed the experience even more if my partner and I had remembered that there were scalpels available for use in the dissection (we had to cut through a very thick ventricular wall with a very small pair of scissors – if you are taking the class and haven’t done the wet dissection yet, REMEMBER that there are scalpels available for use).

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In sum, BI265 was a welcome and intellectually stimulating challenge. I absorbed a great deal of anatomy and physiology in the last four weeks, worked with wonderful classmates and a great professor, and learned about myself, my study and lifestyle habits, and stress management. I would recommend this class to anyone interested in thinking and in challenging his/her intellectual limits.

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The blood vessel model – my best friend during the weekend before the second lab test.

 

Tags: Bi265j

Danielle Levine: Heart Dissection and MMSA Visit

February 24th, 2015 · Comments Off on Danielle Levine: Heart Dissection and MMSA Visit

Danielle Levine (’15, Biology)

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While taking Introduction to Anatomy and Physiology this JanPlan, I was given the opportunity to perform a wet dissection of a pig heart. Having learned about the surface and blood vessel structural features via the study of powerpoint slides, listening to class lectures, and studying plastic models, the wet dissection gave me the opportunity to view the anatomy learned in an actual heart. Studying a list of anatomical features and seeing pictures of them on paper is a very different experience from actually getting one’s hands “dirty” and exploring a real heart and seeing what those structures actually look like.

Besides being able to dissect the heart in lab, one of my favorite activities of the semester was when during the following week we dissected another pig heart with visiting high school students, and were able to show them everything we had learned about the heart the week before. On Martin Luther King Jr. Day, a number of high school students from different schools in Maine visited Colby for the day as part of a collaboration between the Maine Math and Science Alliance and the Colby Goldfarb Center; we were able to show the students around the lab and talk to them about anatomy and physiology, as well as help them with potential science fair project ideas.

That day, our class began with a lab practical that covered the eye, the ear, and the nervous and cardiovascular systems before the high school students arrived; after we finished the exam, we met the high school students who would be spending the day at Colby with us. Each lab group of Colby students partnered with two high school students, my group with Cierra, a sophomore from Dover-Foxcroft, and Shea-Lynn, a home schooled junior. After introducing ourselves, we took the high school students on a tour of our lab, showing them all the different models we use to help us learn about human anatomy. In addition, we went over with them the lab practical exam that we just took, explaining what the answers were (of course, we had an answer key, and we had gone over the answers in class after we had finished the exam), and the physiological significance of the various anatomical structures identified. This was a very enjoyable experience, as not only did it reinforce my knowledge of the material, but it also gave me the opportunity to share that knowledge with these students by teaching them a little bit of anatomy and physiology.

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After the lab tour, we had enough pig hearts left over from the previous week, and so we were able to dissect another pig heart, this time letting the high school students perform the dissection while we helped and taught them about the different structures and features of the heart they were looking at – this teaching was reinforced by the use of pictures and models of the heart.

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After successfully dissecting the heart and exploring its anatomic features (and after lunch), we talked about potential Maine Science Fair project ideas for Cierra and Shea-Lynn; they came up with some interesting topics such as the effect of emotions on heart rate and blood pressure. The day was very rewarding, as it gave me a feeling of competence in that I was able to teach others material I had learned in the course – not to mention, it was also a lot of fun!

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Pictures of two of the heart models we used to study the cardiovascular system and teach the high school students with.

Tags: Lab · Special Activities

Chris Lee: Dissecting a Sheep Heart

February 23rd, 2015 · Comments Off on Chris Lee: Dissecting a Sheep Heart

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I cut the plastic bag open and was immediately hit with a strong odor. Inside the bag was a sheep’s heart, sitting in a pool of preservative chemicals. Immediately after taking the heart out, I went over to the sink to rinse off the chemicals. I could tell that this was going to be a messy lab. Still, I was excited to do a sheep heart dissection because it was an opportunity for me to see a real heart. For about a week, I had been studying diagrams and models of hearts, but not a real version of the organ itself. The anatomical models we used were helpful in learning where structures of the heart are located, but nothing beats seeing the real thing.

After washing the heart, my lab partner and I located its apex (tip) and figured out where the left and right sides were. It was immediately apparent that not all the structures were intact which was unfortunate (both the inferior and superior vena cava had been cut off). However, we discovered a well-preserved depression known as the foramen ovalis behind the right ventricle that had not been damaged in the preservation process of the heart. The foramen ovalis marks the former sport of the foramen ovale, a hole in the pig fetus’s that helps with blood circulation. After the pig’s birth, the hole is sealed, leaving behind the foramen ovalis.

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Next, we started cutting the heart open. Cutting through the walls of the heart was difficult. The heart’s function, to pump blood throughout the body, requires it to be a tough, durable organ and I was reminded of this as my lab partner and I tried to cut through its walls. Pulling apart an incision on the right side revealed a small chamber with a hole in its lower end covered by three flaps. This was the tricuspid valve, the covering between the hole connecting the right ventricle and right atrium. I stuck my fingers through the valve, pushing my way past the three flaps into the larger space known as the right ventricle and felt around. Brushing against my fingers were the stringy cordae tendinae that connected the flaps of the tricuspid valves to the papillary muscles.

Over on the left side of the heart, we saw structures such as the left atrium, bicuspid valve, and the left ventricle. While making a cut on the left side of the heart, I immediately noticed how much thicker the muscular walls were on this side. Something that occurred to me during this dissection that I never really thought about before was how the heart’s form fit its function. Its thick, muscular walls (particularly on the left side) gave it the necessary power to pump blood to different parts of the body. The cordae tendinae, though somewhat thin and stringy, still felt strong and durable, which was necessary for them to be able to keep the bicuspid and tricuspid valves shut. Even the layout of the heart itself is essential to its function. It contains four chambers linked by a straightforward path that enables deoxygenated blood to enter, get pumped to the lungs to pick up oxygen, return, and then get pumped to other parts of the body. The sheep’s heart dissection was definitely my favorite activity from anatomy class. I enjoyed the hands-on aspect of it and being able to explore the layout and structure of a real heart.

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Tags: Bi265j · Lab

Lauren Shirley: Cardiology: Getting to the heart of the matter

February 22nd, 2015 · Comments Off on Lauren Shirley: Cardiology: Getting to the heart of the matter

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One of the highlights of my experience in BI265j was the cardiac section and in particular, the heart dissections we got to do. I had a fairly solid understanding of the heart coming into the class from my EMT training. I knew that the blood came into the heart through the vena cava entered the right atrium passed through the tricuspid valve to the right ventricle, was pumped to the lungs through the pulmonary arteries to receive oxygen and then returned to the heart through the pulmonary veins into the left atrium then through the mitral valve to the left ventricle and out to the ret of the body through the aorta. What my EMT training had failed to teach me, however, was the beauty of this process, which is almost artful in its simplicity and elegance. This class gave me a greater appreciation of the elegance of the heart and the mechanisms behind its continuous beating. I was fascinated by the spread of electrical signal and its motion through the myocardium. The depolarization starting at the sinoatrial node, which spreads to the atrioventricular node then through the bundle of His and out to the Purkinje fibers is a highly linear path, simple yet powerful. While the lecture on the heart and studying plastic models in lab fascinated me, it was the opportunity to dissect the heart that truly solidified by understanding of it.

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We dissected preserved cow hearts. Initially, I was impressed by the thickness of the muscle in the heart walls. It took quite a bit of work with a scalpel and scissors in order to get down into the different chambers of the heart. The sheer thickness of the walls and the work it took to get through them spoke to the sheer power of the heart as a muscle and the strength needed to supply a large body, such as a cow, with blood. Once inside the heart, I was fascinated by the sheer strength of the chordae tendinae, the fibers that keep backflow from occurring in the tricuspid and mitral valves. Despite pulling on these relatively thin cords, they didn’t tear! This further illustrated the necessary strength of the heart to me and the great pressure and quantity of blood that it pumps.

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While it was really exciting to get to see a real life illustration of the models we had studies (that wasn’t color coded), it was even better to have a chance to share our newfound knowledge of the heart with the high school students who visited. I felt that teaching them what I knew solidified it in my mind. However, it was also exciting to see the “next generation” of young science students and how fascinated they were with the human body and its functions. I felt that my enthusiasm for cardiac function was almost contagious as I eagerly showed them how to dissect ad encouraged them to explore and understand the heart in front of them.

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Long story short, this class got me pumped for cardiac anatomy and physiology and a possible career in cardiology. Ironically, I love the heart!

Tags: Bi265j · Lab · Special Activities

Allison O’Connor: Heart Dissection

February 22nd, 2015 · Comments Off on Allison O’Connor: Heart Dissection

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Although I took a lot of science classes in high school, I never had the opportunity to do any dissections. Dissections were always something wanted to get to do because I feel like the best way to learn is through hands on experience. I first fell in love with anatomy in middle school when I visited the Body Worlds exhibit while it was in Philadelphia. My dad took me to this exhibit expecting that we would walk through quickly, but instead we were there for hours as I stopped and closely examined every part of the exhibit. This exhibit was the closest I ever got to dissecting anything before this JanPlan, but the exhibit definitely inspired me to want to learn more about anatomy.

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In my various science classes and in my emergency medical technician training I had learned about the basic structure and function of the heart. Numerous times I have been asked to trace a drop of blood through the heart and it is something that I could recite in my sleep. When we started the cardiovascular unit in anatomy and physiology this JanPlan I thought I was going to hear the same spiel about the heart that I had heard so many times before. However, this JanPlan, I saw the heart in a whole new light. Though I had already learned the basic function before I learned about the anatomy in much more detail this month than I had in the past. I also learned more about the electric conductance system of the heart and some very basically how this presents itself on an EKG, which is particularly interesting to me since I see EKGs done by the paramedics on the ambulance all the time.

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The heart and its function have always been interesting to me, however, I did not fully understand how truly amazing the heart and its structure are until I was holding the pig heart in my hands. While the heart was in my hands I was able to identify the structures that I have learned about so many times and really see for myself the relationship between the structure of the heart and its function. Being able to literally stick my fingers through the arteries and veins to feel where they went lead me to understand the structure of the heart on a whole other level. I was amazed at how muscular the walls of the heart actually are. You are always told that the heart is an incredibly strong muscle, and it is a fact that you just blindly accept as true, but holding the heart in my hands and trying to cut through the muscular walls really showed me the true strength of the heart muscle. I was also surprised at how strong the chordae tendonae were given the fact that they look no stronger than a strand of floss. I put their strength to the test by pulling on them with lots of force and was unable to break them. The heart dissection reminded me of the importance of hands on learning and learning through discovery as opposed to just blindly accepting things as fact. When you blindly accept things it is easy to lose sight of the intricacies and wonder involved in the systems around us. I was in awe during the entire heart dissection and it really changed the way I thought about the cardiovascular system and reminded me of the importance of being curious and full of wonder.

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Tags: Bi265j · Lab

Rachel Bird: Heart Dissection

February 22nd, 2015 · Comments Off on Rachel Bird: Heart Dissection

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I know, rationally, that the brightly colored red and blue heart diagrams in the spiral bound textbook on the lab table aren’t entirely accurate. However, I was surprised at how disappointed I was to open the box of shrink-wrapped pig hearts and discover that the entire heart is a homogenous beige color – somewhere in between tea with too much milk in it and the thick clay in the riverbeds near my house. Luckily, that disappointment didn’t last. As my lab partner, Rebecca, and I unsealed the plastic wrap, our first impression of the heart was the smell. Acidic, chemically, headache-inducing: the preservatives that kept our heart from smelling like rotting meat also made the entire lab smell like the inside of a formaldehyde bottle!

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As our noses adjusted, we began our cursory inspection of the heart. Once I was able to get over the bland coloration, our pig heart actually looked remarkably like the textbook model. From the shriveled atria to the rubbery arteries, our pig heart just looked like a small-scale reproduction of the plastic hearts that had been on display on the lab tables all week. Once we oriented the heart with the apex pointing down, Rebecca made the first cut, deftly slicing the heart in half like a bagel. We both gasped. The interior of the large, muscular ventricles was covered in delicate, stringy chordae tendineae! The textbook photos and models mentioned these fibrous bands, but the lightly sketched lines in our reference image in no way prepared us for the network of elastic filaments that criss-crossed through the ventricles. Rebecca tugged at one of the strands, but instead of breaking, it snapped back into place as soon as she released it. Those things are a lot stronger than they look!

Our second surprise was the septum’s thickness. We had both memorized the fact that the left ventricle has stronger muscle walls than the right ventricle (because while the right ventricle only pumps blood back into the lungs to get oxygenated, the left ventricle has to distribute blood to the entire body). However, the difference was huge! The septum was thick and muscular and not at all thin like the cartilaginous septum that separates the nostrils. As we continued to hack away… or rather, “dissect,” our heart, we noticed that if you pulled the filmy visceral pericardium away from the outer walls of the heart, it revealed rougher, almost striated muscle tissue below. It was even possible to pull up small strands of muscle tissue with the tweezers and separate the layers of the heart muscle. The same was true of the interior of the ventricles – once we peeled back the smooth endothelium that protected the inner walls of the heart, the coarser muscle tissue was revealed.

Even more interesting than the layers of the heart muscle was the layered structure of the veins and arteries splaying out of the heart. After Rebecca and I had thoroughly examined all the entrances and exits to the heart (mostly by sticking our fingers in the tubes to figure out which chamber each one led to), we sliced off a section of the aorta and attempted to identify the layers of the tissue that compose an artery.

By the time we were finished, our pig heart lay in chunks all over the dissecting tray. Rebecca was poking one end of her tweezers through the coronary artery and I was still stubbornly trying to “de-fat” the right atrium. As class time ran out, we reluctantly cleaned up our heart and threw out our gloves, eager to get the scent of preservatives off our hands. As Rebecca and I threw out the last of our paper towels, I turned to her and said, “I hope they aren’t serving pork carnitas again at lunch. I don’t really think I can imagine eating pork after that…”

 

 

Tags: Lab

Mayra Arroyo: The Heart Dissection

February 22nd, 2015 · Comments Off on Mayra Arroyo: The Heart Dissection

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The activity I enjoyed the most during this class was the pig’s heart dissection. As a student, I, sometimes forget that the diagrams and figures in textbooks are only a close resemblance to what things actually look like. This is especially true when dealing with the human body. Diagrams are usually different colors and are embellished to in order for students to learn them more easily. At first it was a challenge to find the parts of the heart I had only previously learned via diagrams. There were many times I could not find the correct anatomy for examples the pulmonary vein and the aorta looked very similar on the real heart, so it was hard to distinguish between them. Another thing I did not realize is the strength and thickness of the heart’s wall. At the start of the dissection I was extremely cautious of how deep I cut into, but I started to realize that the heart was very thick and strong. This activity showed me that the heart is truly amazing part of the body, which the diagrams did not do justice.

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One of my big triumphs during this activity was locating the coronary arteries on the pig heart. Although by just looking at the outside of the heart it is possible to see where they are, but we were able to see where they connected to the aorta and where they extend away. We were able to stick a probe and follow them. We removed some of the fatty tissue to see a clearer view of the arteries. It was amazing to see these arteries, because at that point I knew my presentation was going to be about coronary artery disease and its possible treatments.

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Dr. Klepach told that class that you do not really know and understand material until you teach it to another person. I had the great pleasure to put this idea to the test with the heart dissection. We showed high school students how to dissect the pig’s heart. This was a great learning experience for me, because I was able to solidify the anatomy I already knew, and it also taught me what I had missed the first time. This was by far the most useful part of this activity for me, and the most valuable. I became a full believer in this idea, and will continue to use this strategy in my future studies.

Before this unit I knew only very basic concepts of the heart’s function and its anatomy, but after this activity and lecture my knowledge increased greatly. I am biology major with a concentration of neurobiology and I thought I wanted to go into the neuroscience field, but after this unit I am seriously considering going into the field of cardiology. This is a very challenging topic, but it can potentially be a very rewarding subject for me. There is still a lot I do not know about the cardiovascular system, but I am eager to learn much more about the heart and it’s importance to the human body.

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Tags: Bi265j · Lab

Michaela Swiatek: Pig Heart Dissection

February 25th, 2013 · Comments Off on Michaela Swiatek: Pig Heart Dissection

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During our dissection of a pig’s heart in lab, our class learned a great deal while doing this hands-on activity.  Most students were able to dissect their own heart, and several students shared a heart.  The first incision we made was  along the right side of the heart.  The right ventricle we identified by squeezing the heart.  We were able to do this because  the myocardium on the right side is much less rigid than that of the left ventricle.  This incision allowed us to see the tricuspid valve and the right ventricular outflow tract which includes the pulmonary valve.

Our second incision was into the right ventricle, which had to be cut open from the apex of the heart towards the top.

The next incision was into the tricuspid valve, which allows blood to flow from the right atrium into the right ventricle when the heart is relaxed during diastole.  I learned that when the heart begins to contract the heart centers a phase called systole, and the atrium pushes blood into the ventricle.  Then, the ventricle begins to contract and blood pressure exceeds the pressure in the atrium, the tricuspid valve snaps shut.

I was surprised to learn that a pig’s heart is very similar to the human heart in anatomy, size and function.  In fact, its excellent availability in most areas of the world, along with the similarities to the human heart, make porcine heart tissue ideal for transplant into receipt’s body, in the same way that a human’s donated organ would be rejected.  To prevent this, porcine heart valves are treated with glutaraldehyde to reduce their immunogenicity.

•I already knew that the muscle of your muscle is called the myocardium.  Most of the myocardium is located in the ventricles which are roughly the size of your fist.  The porcine heart, like a human heart, has four chambers and four valves.  Blood flows through the pig heart in the same manner as through a human’s.  This picture show’s the pig heart from the front, with the portion on the right of the picture being the left side of the heart vice versa. The aorta is clearly visible at the top, with the atrium on either side, while the ventricles are in the bottom left.
•Last, when the heart is contracting during systole, the pulmonary valve is open because the blood pushes the cusps out of the way.  Furthermore, at the end of the systole, the ventricles begin to relax and intra-ventricular pressure drops.  When the ventricular pressure drops to below the pulmonary artery pressure, the pulmonary valve closes and prevent back-flow of blood into the ventricle.
•I was surprised to learn that a pig’s heart is very similar to the human heart in anatomy, size and function.  In fact, its excellent availability in most areas of the world, along with the similarities to the human heart, make porcine heart tissue ideal for transplant into body’s receipt body, in the same way that a human’s donated organ would be rejected.  To prevent this, porcine valves are treated with glutaraldehyde to reduce their immunogenicity.
•I already knew that the muscle of your heart is called the myocardium.  Most of the myocardium is locate in the ventricles which are roughly the size of your  fist.  The porcine heart, like a human heart, has four chambers and four valves.  Blood flows through the pig heart in the same manner as through a human’s.

Tags: Lab