Conclusion:
The aim of my experiment was compare the differences in height of males and females in years 7 and 11. My hypothesis stated that “females in year 7 will be taller on an average than males; however I believe that in year 11, males will be moderately taller.” As you can see from my results and graphs, my hypothesis was proved partly correct. On the histogram which compares heights, year 11 males have an overall higher height value bar than that of the year 11 girls, which confirms that the males are taller in their later age of teen years. On the histogram which compares heights of year 7 males the bar is overall at a fairly similar height value than that of the year 7 females. From my results table and average height graph you can see that the average height in year 11 males was 177.30 which was 13.86cm bigger than that of the year 11 female average heights, reinforcing my hypothesis. The average height in year 7 males was 150.22cm which was 0.52cm bigger than that of the girls average heights, this was because of an experimental error. There were eleven year 7 male height measurements taken, which resulted in a higher average. Therefore if a new average with 10 students from year 7 was taken it would have been lower, but still near the average year 7 girls height.
I am now going to use my scientific knowledge to explain my results. The male growth spurt begins later, accelerates more slowly, and lasts longer. The beginning of the increase in growth velocity is about age 11 in boys and 9 in girls but varies widely from individual to individual. The peak height velocity occurs at a mean of 13.5 years in boys and 11.5 years in girls. This is why on average the years 7 boys should have been shorter as they were just starting puberty, from the average of my results this hasn’t been proven but if we look at individual results, two year 7 females are evidently at taller heights above 160.0cm where the tallest year 7 male is 159.0cm. Adult men are on average about 13.0cm taller than women. Most of this sex difference in adult heights is attributable to a later onset of the growth spurt and a slower progression to completion, a direct result of the later rise and lower adult male. From my results we can see that this fact has been proven correct as the average height in year 11 male was 13.86cm bigger than that of the females.
I can now say that if the experiment was carried out to a more highly developed level my hypothesis would have been proved fully correct. I believe that females in year 7 will be taller on an average than males; but in year 11, males will be moderately taller primarily because of the 2-year delay in bone closure as compared to females.
Evaluation:
Overall I think I carried out the experiment fairly well. However in an ideal world there could have been a few things that I could have done to improve my experiment. I firstly could have a larger number of people to take height measurements from, for example fifty different people from each year to take measurements from, e.g. 25 females and 25 males. This would provide me with a larger range of results to focus on and analyse. There were two factors that could have had a slight effect on my results. When the year 7 males and females measured there heights they rounded there results up to 0.5 of a centimetre or they rounded down to the nearest centimetre, this would have affected the overall average. Also there were eleven year 7 male height measurements taken, which resulted in a higher average. An equal amount of height measurements should have been recorded. If I could have controlled all these variables I think I would gain a much more precise set of results.