There will be the slowest reaction at 10degrees. This is because the enzyme and substrate particles vibrate slowly at a low temperature. This means there will be very few collisions – less enzymes and substrate complexes formed. At the highest temperature (50degrees) the enzyme will be denatured. This is because at a higher temperature, there are more particle collisions and the enzyme will change its shape and the substrate will not fit. This is demonstrated as the lock and key method.
Results:
Test tubes Temperature of water Time taken Average
( ) ( ) time taken for film
to go clear (in secs)
1 10 531
2 10 536 533
3 20 435
4 20 442 438
5 30 319
6 30 331 325
7 40 246
8 40 238 242
9 50 270
10 50 286 278
Conclusion:
My graph provides me with the information that trypsin works best in alkaline conditions, at the temperature of 40degrees. This is because, as predicted, it is closest to the body temperature (37degrees). Trypsin is found as an enzyme in the small intestine, hence the best result being 40degrees.
There is a pattern in my results because, as the graph shows, the farther away from body temperature, the less effective the trypsin is. This is due to the lack or too much movement of the trypsin particles. Too high – the trypsin is denatured, too low – not enough particle collisions. The enzyme and substrate particles vibrate slowly at a low temperature which means fewer enzymes and substrate complexes formed. The same with a higher temperature but because there are more collisions, the enzyme will change its shape and the substrate will no longer fit.
Evaluation:
I believe that my results are pretty accurate. The temperature of the water may have been a degree out, especially when recording the higher temperatures, as the water cools rapidly at higher temperatures.
I did notice that I took the temperature of the water in the beaker and NOT the temperature of the actual enzyme. The trypsin would have been cooler and maybe an inaccurate result.
I think that my method was pretty clear and accurate but there is always room for improvement. Instead of getting the water straight from a tap and keep mixing it to get the correct temperature, I could use a Bunsen burner to heat quickly, to save time, or I could possibly use a hot plate to keep the temperature at a constant heat. There aren’t any results that immediately stand out as wrong results, therefore my experiment was accurate.
I do think that my results are reliable because even if I was to do the experiment again, using temperatures nearer to body temperature, I would still get a firm conclusion. This conclusion being, that trypsin is most effective at 37degrees (body temperature). This is because trypsin is an enzyme found in the body.
If I was to do this experiment again I would:
- Use a water bath instead of a beaker, so that the water would remain at a constant temperature at all times.
- Make sure that all of the pieces of photographic film are precisely the same size, as that may have affected my results slightly.
- Record results at 60 and 70 degrees to prove that my theory works (the farther away from 37degrees the temperature is, the longer it takes)
- Take more results around 37degrees to see if the trypsin does actually work best around body temperature. This would cause the curve on my graph to fall lower and curve more. This I have highlighted on my graph.
- Find a more accurate way of testing that the photographic film has gone clear. I could possibly take it out of the beaker after the experiment, and shine light through it and see if it is totally clear. This would help me to record my results accurately.
To gain a more accurate graph, I could maybe use units going up in 5degrees. The points would be easier to defy and would be closer together.
