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Biology Practical notes!!

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Can anyone pls tell what 'a detailed diagram' is suppose to contain. I am confused whether organelles should be drawn or not. Or is it just a plain plan diagram as well?
 
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NO ..organelles.....i think u r referring to high power diaagram...which should show indiviual cells including shadow.....and cell wall cn be labelled as well as nucleus if seen bt not any othe part.......
 
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does anybody happen to have bio p3 and p5 nov 1999????? paper as well as teh marking scheme!!!!
 
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Ok Duh we're getting urease & urea tomorrow in Bio 33, Now what wud be the Improvements, Sources of error & Limitations for the experiment below?
Enzyme Concentration

In this investigation, we will examine what happens to the rate of a reaction when the amount of enzyme is reduced. We will use urease, an enzyme that converts urea to ammonia. The ammonia causes the pH of the water to increase (it becomes more basic). You will be able to tell when a reaction occurs because the urea solution also contains a pH indicator that is becomes yellow in acid but turns red when the solution becomes basic.

The object of this experiment is to measure the amount of time it takes for the solution to turn red if less enzyme is used.

C1. Create a hypothesis regarding the the amount of urease and the rate of reaction of Urea.

C2. Obtain four test tubes and add 2 cm of urea to each.

C3. Label three of these tubes 1 through 3; the remaining tube will not be used; it will serve as a control.

C4. Have your lab partner start timing as you add 15 drops of urease to tube #1 and then swirl the tube until it changes to a red color. Record the amount of time that it took for the urease to change to a red color.

C5. Add 5 drops of urease to tube #2 and then swirl the tube until it changes to a red color. Record the amount of time that it took for the urease to change to a red color.

C6. Add 1 drop of urease to tube #3 and then swirl the tube until it changes to a red color. Record the amount of time that it took for the urease to change to a red color.

C7. Record your results in the answer sheet.

C8. Did using less enzyme produce a reaction?

C9. What was the effect of using less enzyme in your experiment? If your experiment did not work as expected, what should have happened?

C10. In general, what happens to the rate of reaction as the amount of enzyme is decreased?

C11. Do your results support your hypothesis? Explain.
 
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hey guyz recent info i got for u ppl for chemistry ppr 33

my class fellow get information that FA1 is ammonium iron salt for heating, Q2 is reaction KMnO4 with KI in the presence of H2SO4, then titration with Na2S2O3...and Q3 contain Ammonium Bromide and zincsulfate salts.....
 
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hi
i appreciate the notes you gave the other day and they really helpd me.i did bio for the last two month and taking part in may/june exam. that really helpd me. however i want to ask you if you have notes on biology paper5,please post them...i have no notes for this paper....actually not yet done that part of bio syllabus...
thnx a million tym....
 
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@qwertysaad im sorry, im an AS student and therefore dont hav paper 5 this time, btw these notes are collected from mark schemes, just collect notes frm different years of marking schemes! :)
 
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