INTERNATIONAL BACCALAUREATE ORGANIZATION

Diploma Program

San Ignacio de Recalde School

Lab Report

Measuring changes in body temperature

Candidate’s Name: Arturo Valdez Aguilar

Code: 002624-021

Biology – Standard Level

Diploma Session: November 2012

LIMA – PERU

1. Introduction

Body temperature is a measure of the ability the body has to vary its levels of heat. When someone is too hot, the excess heat is carry to the skin’s surface by dilated blood vessels. If this happen, sweat may occur, and while it evaporates it helps to cool the body.

On the other hand, when someone is too cold, its blood vessels contract so the reduced blood flow helps to conserve body heat. In these occasions, shivering may occur. Temperature can be measured in several locations of the body but the mouth and armpit are the most common ones.

The normal body temperature is stated to be 37 degrees Celsius. However, during exercise it increases to almost 40. This happens because mitochondria help nutrients and oxygen from the body turn into energy. During exercise, energy is produced and about 75 percent of it is lost as heat. This heat, from the muscles, move to the blood throughout the body, making body temperature rise.

In this experiment I will test the changes in body temperature right after doing exercise. For this, I will test a group of teenagers who regularly exercise and a group of teenagers that don’t. Both groups will have male teenagers, the difference is that the subjects on the first group realize physical activity as part of their everyday routine (cardiovascular activities as running, or workout in the gym), whereas the subjects of the second one rarely (one or two days maximum per week) or don’t do physical activity.

They will perform a series of physical activities that will exhaust their bodies, like jogging and jumping, and compare the results based on their change in body temperature.

a) Research question

Does teenagers who don’t realize physical activity experience a higher change in body temperature after doing it than teenagers who regularly realize it?

b) Hypothesis

Teenagers who don’t exercise are not used to high amounts of physical activities so their bodies will respond in a greater increase of body temperature than teenagers who does exercise.

c) Variables

Independent How often the subject exercises

Dependent Change in body temperature

Controlled The age of the subjects (from 15 to 16 years old) The exercise that will be performed The time for each exercise (60 seconds ± 0.005) The genre of the subjects: male

2. Materials and method

Thermometer Chronometer

1. The subjects were selected based on how often they exercise. 2. Body temperature of the subjects will be measured with a thermometer first.3. They will realize each exercise during one minute without stopping.4. They will rest for a minute and do the exercise again. This will be repeated until

they have done all the exercises three times.5. After that, body temperature will be measured again and the results will be written

on a piece of paper.6. Data gathering will be put on charts.7. A standard deviation and T-test will be done.

3. Data gathering and results

Qualitative data:

Quantitative data:

Subject Body temperature(±0.05 C°)

1 37.2

2 36.6

3 37.0

4 37.1

Subject Body temperature(±0.05 C°)

1 36.8

2 37.2

3 37.0

4 36.7

Subject Body temperature(±0.05 C°)

1 40.0

2 39.0

3 39.5

4 39.7

Subject Body temperature(±0.05 C°)

1 39.8

2 39.7

3 39.0

4 39.7

Subject

Increase in body

temperature

(±0.05 C°)

1 2.8

2 2.4

3 2.5

4 2.6

Subject

Increase in body

temperature

(±0.05 C°)

1 3.0

2 2.5

3 2.0

4 3.0

Standard deviation of the increase in body temperature – Group A: 0.17078251

Standard deviation of the increase in body temperature – Group B: 0.47871355

The value of T Test between Group A and Group B is: 0.81295348.

With this data, we will compare the results with the T- student chart. We need to substrate

two units out of the amount of data used. We used 2 tables, each one with 4 data. So we

will substrate 8 (number of data) minus 2, which gives us 6.

We locate number 18 in our T-student chart, using the tail probability of 0.05.

References

http://firstaid.webmd.com/body-temperature

http://www.livestrong.com/article/361702-why-does-body-temperature-increase-during-exercise/

http://hypertextbook.com/facts/LenaWong.shtml