Sheep Heart Dissection

Q1: What is the purpose of the pericardium?
- The pericardium is the sac outside the heart that connects the heart to the body and protects the heart; it secretes a fluid to lubricate the heart for movement.
Q2: Observe the blood vessels connecting to the heart. How do arteries differ from veins in their structure?
- Arteries differ from veins because they have thicker walls and do not have skeletal muscles to aid the process of "milking", which veins do. Veins are surrounded by skeletal muscles that help push blood through the veins against gravity. Furthermore, arteries have elastic and contractile layers in their walls; the elastic layer expands when the heart contracts and recoils when the heart relaxes, and the contractile layer is smooth muscle that causes vasodilation or vasoconstriction.
Q3: Place your finger inside the auricle. What function do you think the auricle serves?
- The auricles are wrinkled pouches on each atrium, and they each slightly increase the amount of blood that each atrium can hold.
Q4: Observe the external structures of the atria and ventricles. What differences do you observe?
- The ventricles are significantly larger than the atria, most likely because they have to pump blood to arteries that go to the rest of the body, so there needs to be space for a larger volume of blood.
Q6: Draw a picture of the tricuspid valve, including chordae tendinae and the papillary muscle.

Q7: Why is the "anchoring" of the heart valves by the chordate tendinae and the papillary muscle important to heart function?
- The "anchoring" of the heart valves by the chordae tendinae and the papillary muscle is important to heart function because these two structures help the valves function and open to allow blood to flow in from the atrium to the ventricles. If the chordae tendinae and the papillary muscle were not attached to the heart, the valves would not be able to function properly.
Q8: Using pictures and/or words, describe what you see.
- I see the bicuspid valve in between the right atrium and right ventricle, which were smaller than I expected. There are two clear flaps/cusps with the chordae tendinae attached to them, which are also attached to papillary muscles that stick out from the walls of the chambers of the heart.
Q9: What is the function of the semi-lunar valves?
- The semi-lunar valves prevent arterial blood from re-entering the heart, so it continues to be pumped around the body.
Q10: Valvular heart disease is when one of more heart valves does not work properly. Improperly functioning heart valves can lead to regurgitation, which is the backflow of blood through a leaky valve. Ultimately this can lead to congestive heart failure, a condition that can be life threatening.
a. If the valve disease occurs on the right side of the heart, it results in swelling in the feet and ankles. Why might this happen?
- This might happen because a valve malfunction may cause blood to back up in other parts of the body. This may results in fluid buildup and cause swollen hands, wrists, feet, and ankles.
b. If the valve disease occurs on the left side of the heart, what complications would you expect to see?
- I would expect to see complications in the lungs, because the left side of the heart deals with the blood that is delivered to the lungs; there may be fluid buildup in the lungs.
Q11: Using pictures and/or words describe what you see.
- I see the bicuspid valve, which leads into the right ventricle. Then, the right ventricle curves up and I see the aortic semilunar valve, which has 3 cusps and leads into the aorta. I also see the coronary arteries on the anterior surface of the heart, since they are the main arteries that supply blood to the heart itself.
Q12: Describe how the left and right sides of the heart differ from each other.
- The left and the right sides of the heart differ from each other because the left side of the heart deals with oxygenated blood and the right side of the heart deals with deoxygenated blood. Furthermore, the left side also delivers blood through the aorta to the rest of the body, and the right side delivers blood through the pulmonary trunk to the lungs.
Q13: Draw and label all structures visible in the interior of the cross-section.

Link to our sheep heart dissection: https://www.youtube.com/watch?v=D5BNrrg4xrM

Monday Wellness Reflection: Guided Imagery

This Monday, my friend, Eric Sze, and I presented a beneficial health trend called guided imagery to our class. We chose this topic because our teacher had recently introduced a concept called “mindfulness” to us. Mindfulness is the phenomenon in which a person is aware of their every move and breath, essentially a form of meditation. Furthermore, at the start of class every day, the entire class participates in a short form of meditation by listening to a bell ring, closing their eyes, and breathing deeply until the ring can no longer be heard. The most interesting things that I learned while preparing for this presentation were that it actually increased certain white blood cell counts and is very commonly used in hospitals and therapy centers all over the world. When I was researching the physical benefits of guided imagery, I discovered that guided imagery increased levels of T-cells and natural killer cells, both types of white blood cells, for breast cancer patients. I also learned that many hospitals and therapy centers use guided imagery to help their patients cope with pain and treatment that they are receiving. My topic is important for health and wellness because it can be used so widely by anyone at anytime. The way someone experience guided imagery can be changed depending on how the person prefers it, which means that it can be altered depending on the person’s problem/condition. Because of that, it can be used to help cancer patients deal with pain and treatment, but can also be used on a daily basis to reduce stress and pressures of daily life. It can also be used to improve performance, whether it be mental or physical; it can improve memory and mental agility, but it can also improve sports performances. For example, famous Olympic swimmer Michael Phelps is known for thinking of a calm and relaxing place and taking deep breaths before competing in a big race. On a scale of 1 to 10, I would give myself a 9 because I think I contributed a fair amount of work into the powerpoint presentation and tried to involve the class in the activity. However, I feel as if I could have contributed more to the powerpoint in terms of content; I contributed mainly to the content of the activity and the anatomy of guided imagery, but my partner contributed the transition slides and technological aspects of the presentation, such as the insertion of video links and sources. I think that guided imagery is a very important form of meditation that should be weaved into a person’s daily schedule due to its effectiveness. Guided imagery can take as long as one wants, whether it be one minute or two hours. However, although guided imagery can be made short, reducing duration does not reduce the effectiveness of guided imagery. In the documentary about mindfulness that we watched during class, I learned that even big corporations like Google use meditation and variations of guided imagery every morning before everyone starts their work; the Google executives truly believe that these few minutes of meditation improve their performance throughout the day. Overall, guided imagery is a great technique that everyone should try to experience at least once in their lifetime!

Powerpoint: https://docs.google.com/presentation/d/1JMyUBnP6vkWn9Sko1xTnXCH3X8GZRDSxJ-ZAYUEkQeA/edit?usp=sharing

Unit 3 Reflection

Unit 3 of Anatomy and Physiology was all about the circulatory system and the different diseases that can affect the circulatory system; this included all of the main components of the circulatory system and its connections to other organ systems in the body. The cardiovascular system is made up of the heart, arteries, veins, and most importantly, blood. The heart is the body's battery that circulates blood around the body and delivers nutrients and oxygen to the tissues in the body.

Furthermore, the circulatory system also disposes of waste material from cells. The heart receives oxygen-rich blood from the lungs and is distributed to the rest of the body; the heart also receives oxygen-poor blood from the rest of the body and brings it to the lungs to dispose of carbon dioxide and other wastes collected. Cardiovascular health is the well-being of the functions and organ of the circulatory system, making sure that there is no disease present and that the person maintains a healthy lifestyle. However, many people in the world suffer from cardiovascular diseases, such as heart disease and stroke. Heart disease, which comes in many kinds (heart attack, aneurysm, atherosclerosis, etc.), is mostly caused by an unhealthy diet, lack of exercise, family history of heart disease, and unhealthy habits like smoking and drinking.

Stroke occurs when atherosclerosis or an aneurysm are present in the brain, cutting off circulation to a certain area of the brain. Since atherosclerosis and aneurysms are also considered as heart diseases, stroke is also caused by many of the factors that cause heart disease. In order to promote cardiovascular health, one should maintain a healthy lifestyle by controlling blood pressure and cholesterol, eating a healthy diet, exercising regularly, and managing stress. After finishing this unit, I still want to learn more about how HDL cholesterol clears up LDL cholesterol from clogging up the arteries. I also want to learn about the public's common misconceptions of atherosclerosis and other forms of heart disease, so I can inform people about them in order to promote cardiovascular health.

In this unit, I had trouble remembering the path of blood throughout the heart and the body; specifically, the fact that the pulmonary artery contains oxygen-poor blood confused me, since arteries typically carry oxygen-rich blood. However, I thought that I was more engaged in this unit since learning about all of the different types of cardiovascular diseases fascinated me; learning how to prevent them will also be beneficial in the future. Because of that, I thought that I retained the most information about the different cardiovascular diseases and was the most strong in that aspect. From the labs and activities from this unit, I learned that it is very hard to work on a collaborative project unless you assign each person in the group to a specific job/responsibility. For example, when we dissected the sheep heart for a lab, each person was assigned a responsibility, so the process went along quite smoothly.

My Unit 2 health goals were mainly to reduce my intake of carbohydrates and pearl milk tea and sleep at a more regular time every day. Personally, I think I have actually increased my intake of carbohydrates and pearl milk tea due to the heightened levels of stress from schoolwork and extracurricular activities. However, I do think that I have slept at a more regular time since I set my health goals for last unit. For the remainder of the semester, a few goals I have are to stay on top of my schoolwork without being overwhelmed by stress, increasing my intake of fiber/vegetables, and getting more exercising by going outside more.