Alexander Galt Regional High School

Technical and Science Level 3

Physiology of Exercise

Submitted by Byanca Custeau

Date Submitted: May 21st, 2009

Date Performed: May 12th 2009

Lab Section: The human body

Course Instructor: Mr. Shea

Abstract

The reason of this lab was to verify if the measurements of metabolism rates in the body would increase, decrease or stay the same, after doing three different level of activities. This expirement was based on understanding how the different systems in our bodies function. The respiratory, excretory, circulatory, nervous and the digestive system, all have an important role in the physiology of excercise. During this lab five different rates were measured. They were : pulse, respiration rate, diastolic and systolic blood pressure, amount of sweat (if any) and internal and external temperature. The first activity was that one participant per group had to lay down at complete rest for ten minutes. The second activity, which was the mild activity was going for a walk for five to ten minutes. And then, for the third activity the participant had to do an intense activity such as jogging. Immediately after the participant came back from the certain activity the rest of the group had to measure the different rates. After finishing this lab a few errors we noticed. As we were going with this lab the activities got physically harder. So, this means that the rates should of all went higher after each activity. But since the therometer was taken out too quickly the internal temperature got lower during the intense activity. Which means that the real temperature of the participant after doing her third activity was not as indicated in the results. The second mistake was the blood pressure test. There was too much time wasted between the end of the physical activities and the time the blood pressure was taken. These two errors could've been avoided with more rate testing practice.

Introduction

"Metabolism is the set of chemical reactions that occur in living organisms in order to maintain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments.


This experiment measures basic body metabolic parameters:

- pulse
- respiration rate
- blood pressure
- temperature and sweat


The objective of this lab is to measure body metabolic mechanisms in response to different levels of exercise: pulse, respiration rate, blood pressure, temperature (internal and external) and sweat." (Source: Excercise Physiology: Circulation, Respiration and Excretions systems, Agrh Science Level 3: Systems, Document 2009.)

Introduction: Procedures

The three different conditions of activity consists:

- Having a student volunteer laying down at complete rest for ten minutes. (For example: Having them rest laying down in a quiet place.)

- Having a student volunteer do a light activity for five minutes. (For example: Walking at their own rate.)

- Having a student volunteer do a intense activity for five minutes. (For example: Running, or even going up and down the stairs.)

After each activity the metabolic rates must be measured as quickly as possible using: oral thermometer, ordinary thermometer, sphymomanometer (blood pressure gauge), piece of microscope tissue (for sweat), and stethoscope.

- The oral thermometer should use cover slips and/or be disinfected with mouth wash before each use.

Hypothesis

The hypothesis of this lab is that the highest level of physical activity you do, your pulse rate, respiration rate, blood pressure, sweat, internal and external temperature will all be higher. For example: If you are laying down for 10 minutes, sweat will not be as much expected as in the mild activity. The intensity of the activity you do will have an effect on all the systems in your body and make them work harder.

Graph Results of Metabolisms

This is the Pulse graph with the average results based on the low, mild and high level of physical activity preformed.
This is the Resoiratory Rate graph with the average results based on the low, mild and high level of physical activity preformed.
This is the Systolic Blood Pressure graph with the average results based on the low, mild and high level of physical activity preformed.
This is the Diastolic Blood Pressure graph with the average results based on the low, mild and high level of physical activity preformed.
This is the Internal Temperature graph with the average results based on the low, mild and high level of physical activity preformed.
Finally, this is the External Temperature graph with the average results based on the low, mild and high level of physical activity preformed.

Discussion

The circulatory system is the body's transport system. It is made up of a group of organs that transport blood throughout the body. Then the heart pumps the blood, the arteries and the veins which transports it.


The second system that works while we do exercise is the excretory system. It removes and concentrates on the waste products from the body's fluids. It also returns other substances to body fluids as necessary for homeostasis. "Homeostasis is the ability of the human body to maintain a constant internal environment even though the external environment changes."For example, the ability of the human body to maintain constant internal body temperature which is about 37 ^oC. Also to maintain a constant water balance and a constant internal blood sugar balance.The excretory system also eliminates excretory products from the body.

When you are exercising your respiratory system is very important. It responses by your breathing rate increases and you start to breathe heavily. This happens because your muscles need more oxygen so you breathe deep and quicker for a supply of oxygen can get to the muscles. When you finish exercising your breathing rate will decrease and start to recover.


Now, the nervous system is necessary when doing exercise because it is able to make basic motor skills and other skills like sports. The basic five senses of texture, taste, sight, smell, and hearing are by the nervous system. To conclude, the last system we need while doing exercise is the digestive system. It breaks down the food consumed to absorb all of the nutrients and vitamins that the body needs to function.

During this experiment the heart rate increased. The heart pumped blood faster to the whole body, since more oxygen was needed to all respiring tissues and more carbon dioxide needed to be exhaled, especially those in the muscles. When you do higher level of activities your heart force also increases. Despite pumping faster, the heart also pumped more forcefully, leading to more blood circulating with each pump. Therefore, more blood reached tissues in need of oxygen. More breaths are taken, so the transport of oxygen in blood and carbon dioxide to lungs became faster.

In the intense activity there was more sweat than in the low activity. Sweat also acts as a coolant. It is released on the skin and it consist almost completely of water. Water, with its high heat capacity absorbs heat from the body in order to be evaporated, so the body can cool down. The sweat released when the temperature rises cools down the skin. The sweat also removes waste products.

The heart pumps faster when you do higher level of activities because your muscles require more oxygen, which is passed through blood so your heart beats faster to send blood to muscles.

Each cell in the muscles needed more oxygen when doing more work because of increased cellular respiration within the cell. Each cell also required glucose which is part of cellular respiration. Two substances produced during cellular respiration are carbon dioxide and water.


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C₆H₁₂O₆ + O₂ → CO₂ + H₂O + Energy
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Blood is the transport system for oxygen, glucose, carbon dioxide and part of the water. It is a mixture of cells and a watery liquid, called plasma, that the cells float in. It also contains other things like nutrients (such as sugar), hormones, clotting agents, and waste products to be flushed out of the body. Red blood cells (also called erythrocytes) are the most numerous, making up 40-45 percent of the blood, and they give blood its characteristic color. Red blood cells are shaped like tiny doughnuts, with an indentation in the center instead of a hole. They contain a special molecule called hemoglobin, which carries the oxygen. In the lungs, where there is a lot of oxygen, the hemoglobin molecules loosely bind with oxygen. Each molecule of hemoglobin contains four iron atoms, and each iron atom can bind with one molecule of oxygen, allowing each hemoglobin molecule to carry four molecules of oxygen. In the capillaries, where there is little oxygen, the hemoglobin readily sheds the oxygen it is carrying and allows it to be absorbed by the body's cells. The iron in hemoglobin is what makes blood red.




Oxygen in the blood is carried by a system of tubules made-up of arteries, arterioles, and capillaries. Oxygen diffuses from the high concentration in the arterial capillaries into the area of low concentration in the ce ll. Oxygen attaches itself to the erythrocytes that are red blood cells. Erythrocytes contain hemoglobin which is a molecule that contains an iron atom. Oxygen binds itself to that iron atom.


Carbon dioxide diffuses from the high concentration in the cells into the area of low concentration in capillaries around the cell. The capillaries carry the blood rich in carbon dioxide to the venules and then to the veins. The veins carry the carbon dioxide to the upper
and lower vena cava that lead into the right atrium. Once the blood has entered the right atrium, it is pushed through the tricuspid valve i nto the ventricle chamber. It is then pumped to the lungs where carbon dioxide is replaced by oxygen, which makes re oxygenated blood and the process repeats.




Receptors, such as the ones in the aorta, detect the rise in carbon dioxide in the body as the blood leaves the left ventricle. The carbon dioxide receptor examines the level of carbon dioxide in the blood. The receptors send a signal to the respiratory center in response to an increase or decrease in the levels of carbon dioxide.


The respiratory center is located in the medulla oblongata at the base of the brain. The respiratory center , which is part of the central nervous system and part of the autonomous nervous system, sends a signal to the muscles involved with respiration such as the intercostal muscles in the rib cage and the diaphragm to work faster if the levels of carbon dioxide have increased. These signals occur very quickly. During the intense activity level the abdominal muscles were also activated by the respiratory system.

As the muscles around the lungs contract,they enlarge the area around the lungs.The enlarged area around the lungs decreases the pressure in the lungs. The pressure outside the body is greater at that point than in the lungs so air from the outside is forced into the lungs by the difference in pressure. As the muscles relax and return to their original positions, the higher pressure on the lungs forces air from the lungs into the air.


The lungs are comprised of two main sections. The left and the right lungs. Air from the outside enters through the mouth and the nose. It then enters the pharynx into the lungs to then reach the bronchioles and then into the alveoli, where oxygen enters the blood and the oxygen rich blood is transported to the heart. When the blood is being pumped throughout the body, the lungs get rid of the carbon dioxide at the same time (when you exhale).



The results in the experiment indicate that both respiration and pulse increased with higher activity levels. The mean results support the hypothesis. The range in the results can be explained by different levels of strenuous activities, some requiring more oxygen, and by different levels of fitness among the subjects.


It would be worthwhile to add a further dimension to the experiment by analyzing how long it takes the body to resume the normal pulse and respiration to determine when oxygen levels returned back to normal. The hypothesis would be the faster that the subject's pulse and respiration returned to normal, the better is the subject's cardiovascular and pulmonary systems. Another addition to the experiment would be to have some subjects inhale oxygen. The hypothesis would be that the subjects inhaling oxygen would return to their normal pulse and respiration rates faster than subjects who were not provided with oxygen.


The experiment could also test the level of carbon dioxide produced at the different levels of activity. This can be measured by having the subjects blow through a straw into lime water. Lime water turns murky white in the presence of carbon dioxide as done in a previous experiment this year. The faster the lime water turned milky white, the more carbon dioxide the subject must be exhaling.