Unit 3 - The Circulatory System

Mid-Unit Summary

The circulatory system is made up of the heart and blood vessels that travel throughout the body. The function of the circulatory system is to deliver oxygen to body cells and also carry illness-fighting agents. The main part of the circulatory system is the heart which is a muscle that continuously pumps blood. The heart has four chambers (the right atrium, right ventricle, left atrium, and left ventricle) and one-way valves to prevent blood from backflowing. Pulmonary arteries deliver blood from the heart to the lungs and pulmonary veins deliver blood from the body to the heart. The superior and inferior vena cava bring blood from lungs to the heart, and the aorta brings blood from the heart to the body. Arteries carry blood away from the heart, and veins carry blood back. Blood pressure measures the force exerted on the walls of the arteries; normal blood pressure should be 120/80. High blood pressure or hypertension is where blood pressure exceeds 140/90. 

Blood is made up of red blood cells, white blood cells, platelets, and plasma. The functions of blood are transportation, regulation of body temperature and fluid volume, and protection. Red blood cells' main job is to bring oxygen from the lungs to body cells, and they have hemoglobin which allows them to carry oxygen. Anemia is a reduced carrying capacity of oxygen of red blood cells, which results in not enough oxygen getting to tissues leading to tissues dying. Sickle cell disease is a type of Anemia where red blood cells are crescent-shaped and can't carry as much oxygen. There are 5 types of white blood cells: neutrophils, basophils, eosinophils, lymphocytes, and monocytes. All the white blood cells have a job of fighting infection, bacteria, viruses, parasitic worms, and cancer cells. Platelets are cell fragments that initiate blood clotting. 

Veins carry deoxygenated blood from body to the heart. Arteries carry oxygenated blood from the heart to body cells. Arteries have thicker walls than veins, but less volume than veins. Capillaries are tiny blood vessels that connect arteries and veins. Pulse measures the rate at which the heart beats. An aneurysm is a weakened section of a blood vessel wall. 

A heart attack is a shortage of blood supply to the heart. Signs of heart attacks can be chest pain, shortness of breath of nausea. Heart attacks are the #1 cause of death in illnesses. Heart attacks are caused by atherosclerosis of the coronary arteries. Atherosclerosis is the build-up of fat and cholesterol on the artery walls. Atherosclerosis is caused by excess sugars, polyunsaturated fats, and omega-3. 

Unit 2 Reflection

Unit 2 Reflection

Health is keeping the 5 pillars: nutrition, sleep, stress, exercise, and a social life in good condition and making sure each pillar is getting the adequate amount of whatever they need. Health is also keeping the 4 main hormones: leptin, insulin, glucagon, and cortisol in balance.

I don't think I am incredibly healthy, but I am not doing awfully bad. For nutrition, I think I get an appropriate amount of calories on a daily basis, but I eat too much unhealthy food from fast food restaurants. For sleep, I do pretty poorly, because I sleep too late from procrastinating on homework. I think I do pretty poorly in exercise; I take martial arts for about 1 hour a week, but I don't exercise much on my own. However, I think my stress levels and social life are doing okay. i think i get out enough and am with friends for a lot of time in the week. I also think I don't get very stressed about college, grades, or things I should be stressed about. I think that people at SHS do pretty well in nutrition, exercise, socializing but do poorly in sleep and stress. I feel like a lot of SHS students don't get enough sleep each night and overwork themselves. I also think SHS students are very stressed and worried about their grades, college applications, tests, finals, volunteering, and the list goes on and on. I don't think there is too much that could be done to promote health, but we can try assigning less homework or completely getting rid of the finals.

One of the major takeaways I had from this unit was that stress is good for you. Unlike the others, we have always believed that they are good for us, such as sleep, nutrition, and exercise. I went into this unit believing that stress was an extremely negative component, and we should do everything we can to eliminate it. I learned that stress is very important for people to function properly, but we just have to control it, because it's only harmful when the stress remains after the stressor is gone. I also learned that being social and not being social can surprisingly have the same health effects as smoking versus not smoking. Another takeaway that has impacted by daily activity was learning that carbohydrates are a lot unhealthier and cause more weight gain than fat does.

Over the course of the unit, I learned a lot of important aspects of each pillar. Specifically, I learned the importance of fiber and Omega-3 in a person's diet in nutrition. I learned about the amount of sleep and exercise people should be getting. I learned about the alarm stage, resistance stage, and the exhaustion stage, and the different effects of each stage. I still do not fully understand the difference between REM sleep and non-REM sleep. I know that REM sleep happens when your eyes move rapidly, your brain is at its highest level of function, and this is the state where dreaming occurs. One thing that I do not understand is when REM sleep starts and stops and when non-REM sleep comes in. For this unit, one of my major problems was that I was working too slowly on notes, labs, and classwork. Next unit, my major goal for improvement is using my class time and work time more productively to get things done faster and more efficient.

https://www.ted.com/talks/russell_foster_why_do_we_sleep?language=en#t-559054

This TED talk explains why humans sleep. Throughout the unit, we learned a lot about sleep, what happens when we sleep, the function of sleep, and the importance of sleep. But one thing I never really understood is why humans sleep. Sleep takes up 32 years of our lives and is vital for our daily function. Sleep is important for restoration, energy conservation, and proper brain function, but I wondered why we couldn't apply these in an activity besides sleeping. This video explains the important of knowing that a person is getting enough sleep and critical brain functions that are taken care of. This video relates a lot to our unit because it talks about the detrimental health effects when we don't sleep enough. It also mentioned that 100,000 car accidents were due to tiredness and a lack of sleep that was also mentioned in the lecture. 

Chalk Heart Walk

**NOTE: I forgot to mention that the red blood cell enters the heart through the superior/inferior vena cava from the lungs**

In this activity, I learned a lot about the heart that I never knew before. Besides learning just the names of different arteries, veins, and valves, I was intrigued by the number of detailed parts in the organ. I never knew there were different muscles like the papillary muscle or the chordae tendinae, since I always believed the heart was just one big muscle. I also learned about purkinje fibers, which I never heard of, that send nerve impulses to the heart. I also surprisingly learned that blood travels from the body to the heart then to the lungs, then to the heart then to the body, starting over again. I always thought lungs travels to the hearts and back to the lungs, and the body to the heart to the body. I never knew the circulatory system was a complicated double loop. Drawing the heart was also really fun since it's been too long since I've played with chalk.

Blood Pressure Analysis Questions

1) The systole blood pressure measures the blood pressure in the arteries when the heart muscle contracts. Diastole blood pressure measures the blood pressure in the arteries when the heart is relaxing.

2) The stethoscope is used to measure heart rate, or you can feel it in your radial or carotid arteries. The stethoscope and the sphygmomanometer are both used to measure blood pressure.

3) The thumb has a major artery running through it, so you can feel a pulse. Using your thumb can confuse the reading because you can feel two pulses.

4) Attach the blood pressure cuff on and slide the noise sensitive part of the stethoscope under the cuff. Then pump the blood pressure cuff to about 150 mmHg. Then slowly let air out of the cuff. When you first hear a heartbeat through the stethoscope, note the mmHg; this is the systole blood pressure. Continue letting air flow out of the cuff until you can't hear a heartbeat anymore and note the mmHg; this is the diastole blood pressure.

Sleep Diary 

Relate and Review

Over the week of recording my bedtimes, I was surprised to find that I am getting an average of 8 hours of sleep every night, the recommended amount of hours a 17-year-old should be getting. However, I noticed that although I am getting the recommended hours, the hours are unevenly spread over the week. I sleep too much over the weekend and a too little on the weekdays. I learned that when I sleep too much, I actually get drowsy and less energized throughout the day. Because of this, one of the biggest takeaways from this weeklong sleep diary is that I can't completely compensate for a sleep debt.
Another discovery I found was that the amount of sleep has a huge correlation with your alertness during the day. On days where I get enough sleep, the weekends, I am a lot more alert throughout the day. However, on weekdays, I found myself getting less sleep and very fatigued in the afternoon. I learned that sleep is extremely beneficial for long-term health such as cleaning out wastes in the brain. But sleep is also very noticeable in everyday life, because of your alertness. Alertness is an extreme safety hazard, due to the countless deaths and tragedies caused by a lack of sleep.