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.

Measure basic body metabolic parameters:
— pulse,
– respiration rate,
– blood pressure,
– temperature and sweat

The objective of this lab measures body metabolic mechanisms in response to different
levels of exercise: pulse, respiration rate, blood pressure, temperature (internal and
external) and sweat. "

Introduction; Procedures

The three different conditions of activity consisted:

- Having a student volunteer laying down at complete rest for ten minutes.

- Having a student volunteer do a light activity for five minutes.

- Having a student volunteer do a intense activity for five minutes.

After each activity the metabolic rates were measured as quickly as possible using: Oral thermometer, ordinary thermometer, sphygmomanometer (blood pressure gauge), piece of microscope tissue (for sweat), sthethoscope.

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

Discussion *

The physiology of exercise depends on 5 systems to work correctly ; The Respiratory System, The Circulatory System, The Excretory System, The Nervous System and The Digestive System, all of them equally important.

Each cell in the muscles needed more oxygen when doing more physical exercise because of increased cellular respiration within the cell. Each cell also required glucose which is part of cellular respiration. Glucose is produced during the process of breaking down the carbohydrates in your body . Then the digestive system breaks down what you drink and eat to nourish cells and also to give you more energy. The two main substances produced during cellular respiration are carbon dioxide and water. The forumla for cellular respiration is: C6H12O6 6O2 → 6CO2 6H2O Energy.

Blood is the transport system for oxygen, glucose, carbon dioxide and part of the water.Blood is made up of red blood cells,white blood cells, platelets and plasma. 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 cell. 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 venulesand then to the veins. The veins carry the carbon dioxide to the upper and lower vena cava that lead into the right atrium and up and out the pulmonary artery. The carbon dioxide comes back in the heart through the pulmonary veins into the left atrium. It circulates to the left ventricle and out the aorta to the rest of the body. It passes through many different tubes and then reaches the bronchioles. It then goes up in the trachea, into the epiglottis where it is released by the nose or mouth.

Receptors, such as the one 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 receptor sends a signal to respiratory centre in response to an increase or decrease in the levels of carbon dioxide. The respiratory centre is located in the medulla oblongata at the base of the brain.

The respiratory centre , which is part of the central nervous systemand part of the autonomous nervous system, sends a signal to the muscles involved with respiration such as the intercostal muscles in the ribcage 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. This was not part of the procedures so in the next repetition of the experiment this should be included in the procedures as one of the variables to observe.

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 nose and the mouth. The oxygen passes through the larynx (speech sounds are produced there) and the trachea (a tube that enters the chest cavity). In the chest cavity, the trachea splits in two smaller tubes called the bronchi. Each bronchus (plurial of bronchi) the divides again forming the bronchial tubes. The bronchial tubes lead into the lungs where they again divide into many smaller tubes which connect to tiny sacs called alveoli.

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.

Result Graphs of Metabolisms

The pulse rate for low, medium and intense activity is show in the graph below ;














The Respiration Rate for low, medium and intense physical activity is shown below;















The systolic blood pressure for low, medium and intense physical activity is shown below;












The diastolic blood pressure for low, medium and intense physical activity is shown below;











The internal temperature for low, medium and intense physical activity is shown in the graph below;












The external temperature for low, medium and intense physical activity is shown in the graph below;