Mid-unit Summary

During this unit in Anatomy, we have covered the concepts of the heart anatomy/ physiology, blood composition, blood vessel anatomy/ physiology, and cardiovascular diseases so far.

The heart is composed of four main chambers: Right atrium, right ventricle, left atrium, and left ventricle. These chambers allow blood to flow through the heart and be pushed where it needs to go. The heart is covered by the pericardium, which holds the heart in place. The heart also contains valves, which keeps the blood from flowing backwards in the heart. When the heart contracts, the blood pressure is called systole, while the pressure when it relaxes is called diastole.

The circulatory system is used to transport materials that is needed by near by cells and remove waste materials from cells as well. The major organs that compose the circulatory system are the heart, lungs, kidneys, small intestine, large intestine, liver, spleen, and bone marrow. Together, these organs work together to keep the circulatory system functioning. The heart is the main organ running the system. With every beat, it pumps blood in and out of all of these major organs to keep the body functioning.

Blood vessels are used to transport blood towards the heart. Arteries take bloods away from the heart. A disease called atherosclerosis can occur if plaque builds up in a person's arteries. In the article titled "Atherosclerosis: The New View," the author describes how it occurs. It explains that atherosclerosis can occur due to inflammation in the vessel walls, which triggers white blood cells to congregate in that area, which try to consume the fatty deposits in that area. The white blood cell becomes foamy, as it cannot consume that much fat, so it turns into plaque. As time goes on, the cells create a layer of smooth muscle tissue over the layer of plaque, but if it gets reopened it can cause many problems. If the layer of smooth muscle cells cracks, the plaque is released into the blood stream, which causes the blood to clot in the spot of the tear. This blood clot is extremely dangerous, as it can clog the vessel, possible triggering a heart attack.

Blood is another very important thing. It is mainly composed of red blood cells, buffy coats (white blood cells and platelets), and plasma. Blood transports nutrients and waste from cell to cell. It is also used for regulation of pH and body temperature. Also it is used for protection by it clotting and fighting infection. Red blood cells are used to carry oxygen throughout the body. White blood cells are used to fight off microbes.

Heart diseases are the biggest cause of death of people. A heart attack is when the blood supply to the myocardium is reduced, which can lead to heart cells dying. Heart attacks can often lead to cardiac arrests, which is an electrical malfunction in the heart. Often times, atherosclerosis can lead to heart attacks. In the article "A Strike Against Stroke," by Bonnie Liebman, Liebman explains how strokes mostly occur when blood clots form and block the flow of blood. She warns readers to not to ignore the signs of strokes, such as headaches or not seeing out of one eye, as when the stroke occurs, there may not be much time for the person to survive.

Blood Pressure Lab

Systolic blood pressure is the pressure of the blood when the heart contracts and pumps blood out and diastolic pressure measure the pressure when the heart relaxes again. The stethoscope is used to measure the heart rate, while the sphygmomanometer is used to measure blood pressure. Using the thumb to measure pulse is not ideal because the thumb has a pulse in it as well. The sphygomomanometer measures blood pressure by putting pressure on the arm and listening to heart beats when the pressure is released. To take blood pressure of a person, first be sure that all of the air is out of the band. After checking this, double check that the valve is tightly shut. The band attaches to the upper arm and a stethoscope is placed under. Pressure is added to it until the meter reaches 150 mmHg. After reaching this pressure, the valve is opened to allow air to slowly come out. The recorder listens for a heartbeat and marks down when they can heart the first beat. Likewise, when they cannot hear a heartbeat anymore they record that as well. The number that was recorded when the heartbeats went away is the in the denominator of the fraction, while the first number is in the numerator.

Heart Chalk Walk Reflection

In the heart, the deoxygenated blood that comes from the body enters through either the superior or inferior vena cava. It then enters the right atrium and goes through the tricuspid valve, where it comes into the right ventricle. When the right ventricle if full, it flows through the pulmonary valve to go to the pulmonary artery, which takes it to the lungs to be oxygenated. After returning from the lungs through the pulmonary veins, the blood enters the left atrium to then be pushed through the bicuspid valve to the left ventricle. Once the left ventricle is full, it gets pushed through the aortic valve to the aorta, where the oxygenated blood is spread throughout the body.

https://www.youtube.com/watch?v=rHQEsz4CwBg&feature=youtu.be

Unit Two Reflection

Health is the measure of the body's efficiency and overall well-being. Health can be categorized into five main pillars: nutrition, exercise, sleep, stress, and social. Each of these five aspects play a major role in the body's well-being. Four important hormones that control and regulate homeostasis inside of the body are insulin, leptin, glucagon, and cortisol. These hormones work together to maintain healthy glucose levels inside of the body. The four keys to a health diet are adequacy, moderation, variety, and balance. This recommendation basically advises to get a little bit of everything, and not to eat too much of something. Also exercising plays a key role on health. The different types of physical activity are aerobic, muscle-strengthening, bone-strengthening, and flexibility. The amount of time that a person needs to work out for depends on the intensity of which they are performing. The more intense a person is, the less time they need to spend on a certain activity. Sleep is also a critical part of health. Sleep is a time for the body to rest and for the brain to recharge and sort out its thoughts from the day. The two stages of sleep are REM, which is when the body is paralyzed and the brain is very active, and non-REM, where the body is not paralyzed and eyes move more slowly. The next pillar of stress is defined as any event/demand that causes a predictable physiological response. The three main stages of stress are the alarm phase, resistance phase, and exhaustion phase. The alarm phase is the initial "fight or flight" phase where the body reacts to an immediate source of alarm. The resistance phase is more of a long term stress where the body begins to become more impaired. In the exhaustion phase the stress has continued for so long to the point where death can even occur. The social aspect of health focuses on all the benefits of how having a socially active life can lead to many health benefits such as an increased immunity to diseases.

I think that I am somewhat healthy. I wouldn't say I'm perfect, but I think I do think I am healthy overall. I just need to tweak a few things in my lifestyle. For example, in my nutrition analysis I lacked fiber and different vitamins. All I need to do to improve on this is eat more fruits and vegetables in my diet. Also, I want to exercise more often. As of now I am not playing any sports, so I need to run more often on my own. I'd say that I get enough sleep and that I am socially active as well. I would say I am about average on stress, but on the better end of the scale at Saratoga High School. The people at this school are way too stressed and don't get enough sleep. Also, many do not eat a healthy diet since some skip breakfast and eat pizza for lunch everyday. To counteract this school wide problem, teachers should try to communicate on test days or big project due dates. This allows students to not cram multiple subjects in their head the night before the test. It would also help in the sleep category since students would not have to stay up so late just to study. At school, the cafeteria should sell more nutritious foods for lunch instead of the pizza and cup-o-noodles. This would improve health overall around the school.

Some of the key understandings of this unit is what health is and how the 5 pillars of health effect that a person's overall health. Overall, I learned many new things during this unit. I learned the function of the four hormones that effect a person's overall health, and how not eating the right foods can completely destroy the healthy balance of them. From the nutrition section I learned that on average, a person should be drinking half their body weight in ounces of water. In the exercise pillar I learned that one can use the talk test to figure out the intensity of the activity they are doing. I also learned that if you ever feel drowsy during the day that means you have sleep debt. From one of the TED talk videos, I learned that stress is actually good for the body. It means that your body is preparing itself for something and pumping more blood so you are better prepared for it. Lastly, I learned how having a more social life can reduce some cancer developments. One thing that I still do not fully understand is the concept of dreaming. It confuses me on how dreaming occurs in the REM stage, where the body is paralyzed, yet often people twitch when they dream. This counteracts the idea that you don't move when you dream since people do actually move around. One thing that I can improve on next unit is applying what I have learned in this unit to better understand what I am learning next. One job that relates to this unit is the field of neuroscience. In this field, scientists examine the brain and how it functions with the rest of the body. This relates to what we covered this unit since stress and sleep have much to do with the brain. People in neuroscience study and try to understand more and more about the brain. One could look more into the study of concussions, which is very applicable in today's society with many different sports coming up with new rules to protect its athletes. For example, in youth soccer heading the ball has been made illegal to prevent brain trauma at a young age. When a person recovers from a concussion it is important for them not to be under too much stress, since they are prone to headaches. Also sleep is said to be important to recover from a concussion, unlike what the old idea of waking the person up at different times during the night. This shows how the concept of concussions is still unknown, so many take precautions when dealing with it. So much more can still be discovered about concussion and just the brain itself.

https://www.sfn.org/about/about-neuroscience

Sleep Analysis

I monitored my sleep from September 30 to October 4. I think that I could still get more sleep each night. Even though I am pretty alert during the day, an average teenager should be getting at least 9 hours of sleep every night. I currently am getting about eight and a half hours of sleep every night, which is only a half hour below the recommended amount, but I think it would be helpful to still get more. I only drank one caffeinated beverage throughout the whole time of recording my sleep, so that is also good. I was able to stay alert without having to drink any caffeinated things. Overall, I think I get a decent amount of sleep based off of this analysis, and could try to get that half hour more if I wanted to improve on anything.

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