Biology p3!!

[libra94]

question 1 b (i)
http://www.xtremepapers.me/CIE/Internat ... _qp_33.pdf

can we plot like.....starting from 35min on the x-axis while starting from 0 on the y-axis????

 

[aquariangurl]

Yeah, time is on the X axis, Draw the Z thing so that u can show that u're starting from 30, & start the Y axis from 0, If u want me to post how I drew my graph, Temme I'll do it =)

 

[rz123]

yeah u can u need to give slight wave on both axis,and start from 35th minute on x axis and from 1 at the y axis after giving a slight wave ( can't remember the exact word use for this slight wave)

 

[hassam]

bt is shhowing slight wave necessary...????

 

[rz123]

yup i guess on x axis its necessary as u have to start from 35th minute, so a slight wave will indicate the time which is not under consideration 0 to 34,
we require graph from 35th minute onwards.

 

[filza94]

Hey all.. Yhe 4 2mrw We might have Urease... N Transverse Section of leaf.. Hopefully..

http://www.scienceinschool.org/print/607 a link realted to enzymes urease.....

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.