Tuesday, 10 May 2011

Lab 1


-Method
-Results
-analysis
-photo/video
In this practical, we we're asked to investigate the effects of sugar with yeast on cellular respiration.

Materials: 

  • test tubes (5)
  • weighting boat
  • weighing scale
  • sugar
  • yeast
  • spatula
  • breaker
  • test tube rack
  • thermometer
  • graduated cylinder
  • ruler

1.     Prepare the 0.5 grams of yeast using the weight boat as a place to add the yeast. Make sure when weighting the yeast that the tare mode is on to exclude the mass of the weighting boat
2.     Pour the yeast into the individual test tubes and place the test tubes on the test tube rack
3.     Use a graduated cylinder to measure out 10 ml of water into each of the test tubes with yeast
4.     Prepare the sugar on the weighing boats by increasing the amount of grams each time by 1.
5.     Prepare a hot water bath. Make sure that the water bath is at the 34 -27 degree range. 
6.     Once the water bath is ready, pour the sugar into each test tube IMPORTANT: MAKE SURE THAT THE SUGAR IS PUT AT THE SAME TIME FOR FAIR RESULTS.
7.     Record the height of the bubbles for every 5 – 10 mins.  

Changes to the method: We were suppose to use bromothymol blue and  hydrochloric acid as an indicator of cellular respiration, however the solution with the yeast did not respond to the bromothymol blue and the hydrochloric acid. Therefore the height of the bubbles was used as the results for cellular respiration

Faults to the experiment:  Just after 5 mins test tube 1 had a build up CO2 therefore making the cork of the test tube pop. This is because using too much sugar causing it to inhabitable.

2 comments:

  1. Pictures?

    Communication in science is always better when you use pictures. They speak a thousand words, so they say.....

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  2. Knowledge and Understanding: 3
    Thinking and Inquiry: 2
    Communication: 1

    Your knowledge and understanding is fine, you show this with your explanations of labs and of the ETC. Unfortunately, your thinking and inquiry isn't doing too well because you're not reflecting on the outcomes of the labs, you're simply stating them. Communication takes a dive downward because you have some awful grammar mistakes, you hardly use images/charts, and your blog is not up to date. I understand there have been technical issues involved, but couldn't you have solved them earlier by creating a new blog and then just transfering the information?

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