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Plan an investigation to determine which part of a pineapple fruit " stem, flesh or leaves " has the highest concentration of bromelain.

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Introduction

Title of Investigation: Plan an investigation to determine which part of a pineapple fruit - stem, flesh or leaves - has the highest concentration of bromelain. Risk Assessment: Risk factor Risk involved Action taken to minimise the risk involved Gelatin Usually not harmful but for the people who is allergic to the ingredients must stay out. Wear goggles, apron and gloves. Should never attempt to eat. Hydrochloric acid It is corrosive and irritant. The vapours are severally irritating which causes severe burns in the skin but if inhaled Dangerous if the acid in the syringe has been squirt. Contact with eyes, skin Any spillage Should avoid getting contact with the acid by wearing gloves, apron, and safety glasses. Keep the chemical in fume cupboard, close the cupboard and the container lid immediately after use in order to prevent from inhaling the chemical. Avoid using the syringe towards the face rather use it towards the beaker. Wash it immediately in order to prevent this wear safety goggles and a pair of gloves. Must be reported it to the invigilator/teacher and should be completely wiped out from harming others. Glass breakage Handle it with care, use dust pan and brush to clean the surface if any glass had accidently broke. Hot Water bath Might cause burns Stay away after use. Wear gloves and goggles from contacting with hot water and vapour. Bromelain There is no side effect but for the people who are allergic to bromelain might be aware. ...read more.

Middle

7. Placed the film in a small bowl and placed it inside the oven to dry for 5 minutes. 8. Then weighed them and recorded them in a table. Table of results: Mass of the developed photographic film Pepsin 1% Pepsin 3% At the start 0.21 0.20 0.21 0.21 0.21 0.20 At the end 0.18 0.18 0.18 0.18 0.18 0.18 % Concentration Rate of reaction (sec-1) to clarify Experiment Repeat A Repeat B Average 3% Pepsin 22.50 22.50 22.50 22.50 1% Pepsin 35.29 35.51 35.51 35.34 Mass of the undeveloped photographic film Pepsin 1% Pepsin 3% At the start 0.21 0.20 At the end 0.17 0.19 Time it took to clarify 56.20 31.47 Carried out the preliminary work so that we could get knowledge of seeing if the method works and also determined what needs to be kept constant and what need to be changed during the experiment. If the experiment didn't work then is there anything that needs to improve in actual method and also to see the effect of proteases on gelatin and photographic film. The experiment with the jelly didn't work because the jelly kept wobbling when making holes so the measurement of the hole is not constant and when adding the enzymes and HCL some spilled out and some was not inside the hole but ran outside the hole because the amount of the enzyme was excess. The size of the jelly was not right because when taking the jelly out from the container some was spoiled by breaking. ...read more.

Conclusion

Record the time and take the boiling tube with the solution out immediately after 30 minutes to get accurate results. Temperature 55�C Controlled If the temperature is high the particles will collide so the rate of reaction increases but by keeping the temperature constant keeps the reaction constant. Hot water bath set at 55�C. pH at 6.5 Controlled Bromine has pH between 4.5- 6.5 so the optimum pH is 6.5 increase in pH after this 6.5 will cause denature. Same volume of buffer solution. Size of photographic film Controlled To give fair results Measure it twice using ruler after cutting it. Evaluation Even though the experiment seems to be easier but there are some negative things about this experiment. They are: * The leaves of the pineapple long pointed leaves with needle tipped and up curved spines on the margins, which will prick the fingers if not carefully picked. So there is a difficulty when cutting it to put inside the blender to extract the juice. * When separating the stem and flesh because they both are attached to each other so when trying to extract the juice some part of flesh or stem can be in different places. * Maybe increase the temperature more at 5�C because the Bromelain denatures at 70�C when kept more than 5 minutes. I don't think anything else that needs to be changed or improved and I think that my method would produce fair results. ?? ?? ?? ?? GCE APPLIED SCIENCE Unit 4 Cells and Molecules 1/10 ...read more.

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