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Introduction

Biology lab report Aim: To study the effect of age on the reaction time. Hypothesis: I think that the reaction time will increase as I begin to test older people. This is because as we get older, our muscles and organs get weaker and as the muscles (effectors) get weaker, they will need more time to react to a stimulus than the reaction time of younger people as they have stronger muscles (effectors) so they react normally to the stimulus, therefore needing less time to react to a change this is simply because the reflexes of a person are at their best when people are young (teenagers or 20s) so as we get older, our reflexes become worse. Therefore I think that the first age group (10-20) will score the best average reaction time, the second age group (20-30) will score the second best reaction time and the third age group (60 and above) will socre the worse for the reasons above. Variables: 1. Independent: The ages of the people I test. ...read more.

Middle

5. Then, let go of the ruler and your volunteer has to try to catch it as fast as possible. 6. Mark the point on the ruler were the volunteer caught it. 7. Do this to all 21 volunteers. 8. Record your results and find the average for each age group. Data collection Table #1 Age (age group: 10-20) Point (cm) were the ruler was caught Age (age group: 20-30) Point (cm) were the ruler was caught Age (age group: 60 and above) Point (cm) were the ruler was caught 12 20 21 25 60 15 19 26 21 25 62 13 13 22 22 25 65 14 15 25 28 25 69 12 20 28 30 25 66 17 19 28 25 25 67 13 20 28 27 25 63 12 Average (years, cm) 17 years 26 cm 25 years 25 cm 65 years 14 cm Conclusion: As we can see from the results above, there was a major decrease from each age group. The first age group, which was between 10 years and 20 years, had the best reaction time scoring an average of 25 cm for each catch. ...read more.

Conclusion

scored 15cm. The difference here is quite large, it is about 7 cm which means that the reaction time was decreased a lot. As we compare the average reaction time of the highest age (28cm) in the first age group (10-20), and the average reaction time of the lowest age (25cm) in the 2nd age group (20-30) we find out that the difference is very minimum (28-25=3) therefore proving my point in the hypothesis (I think that the reaction time will increase as I begin to test older people) right. Sources of error: 1. The length between the ruler and the hand of the volunteer has to be the same when measured from the lower end of the ruler to his hand. If this wasn't true in the experiment, the point where the volunteer catches the ruler would've varied. Improvements: 1. Measure the same length between the ruler and the hand of the volunteer. This length has to be measured from lower end of the ruler to his hand in order to have a correct and more accurate table of results. You can do this by simple drawing a small line on a wall behind the volunteer, and then use this height while dropping the ruler for all the volunteers. ...read more.

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