• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

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

Extracts from this document...


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.


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.


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.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Molecules & Cells section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Molecules & Cells essays

  1. Marked by a teacher

    An investigation into the inhibiting effect of tomato juice on the germination of cress ...

    3 star(s)

    The graph also shows that the results between 15% and 20% are not significantly different. This shows that the negative effect of tomato juice on germination only significantly increases up to a certain point (e.g. the inhibitors have already taken up most of the active sites so if you add more they will have less of a impact).

  2. Marked by a teacher

    I am going to investigate the ability of Pepsin on Gelatin. I aim to ...

    3 star(s)

    heated to 42?c, one in a water bath heated to 54?c, one in a water bath heated to 61?c, and one in a water bath hearted at 79?c. To make sure the temperatures are constant, the student will place a thermometer in each tube of pepsin.

  1. All flesh is grass.

    Assimilation: - this is the way in which the body incorporates and utilises digested food. Digested food molecules are carried around the body through the circulatory system: they may be stored for future use, such as fat and the formation of glycogen stores; they may be broken down further

  2. Investigating Whether Temperature Affects The Bromelain Enzymes Inside Pineapples By Changing The Rate Of ...

    After the 24 hours of the pineapple juice being in the boiling tube with the gelatin, the liquid will be poured out of the boiling tube into a measuring cylinder and the amount of liquid obtained will be measured. This measurement will then be used to minus 5cm cubed from.

  1. An investigation in to how enzyme ripeness in pineapple affects the setting of gelatine.

    This is also true for enzymes up to a certain point: the optimum temperature. Above this temperature, enzymes vibrate so much that their structure is damaged and the active site altered. A change in pH disrupts the charges; consequently the active site cannot bind to the substrate.

  2. Digestion Of Gelatin On Exposed Photographic Film.

    then we place the thermometer through the cork into the boiling tube. We place the boiling tube into the assigned thermostatically water bath. Then we wait couple of minutes for the trypsin to acclimatize to the correct temperature. As you place your photographic film you then start the stopwatch and

  1. Why doesn't jelly set when fresh pineapple is used?

    Why enzymes cause this to happen. Enzymes are complex protein molecules which perform actions on other molecules whilst they themselves are not used up in the reaction. Enzymes are mainly affected by temperature and pH, and the rate of the reaction is affected by the concentrations of the enzymes.

  2. Catalyse Investigation

    of about 0.5 mm either side), are so large that the results are inconsistent. However, too slow a rate, however low the percentage inaccuracies may be, is impractical, as I do not have all the year to do this in.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work