Cellular Rspiration

Only available on StudyMode
  • Download(s) : 348
  • Published : March 20, 2013
Open Document
Text Preview
LABORATORY REPORT FOR BIO411
Experiment 5 : Cellular Respiration
Experiment 6 : Photosynthesis

Title: Cellular Respiration

Objective: To observe and determine cellular respiration in yeast/onion cells. * Measure respiration rate using different substrates.
* Measure respiration rate at different temperature.

Introduction:
In this laboratory experiment, we are given 3 task. The first one is respiration in yeast. Second is respiratory indicator and the third one is observing mitochondria in yeast/onion cell.
The first experiment is about investigation of sugars yeast. We will determine which sugars yeast can be use for cell respiration. When the yeast undergoes anaerobic/aerobic respiration, they will give out carbon dioxide. After that it will reacts with water to forms a weak carbonic acid solution. We will use BTB to monitor this reaction. Further explanation will be discussed at the discussion.

The second experiment is respiratory indicator. Same concept with the first experiment. We will measure the respiration rate using different substrates based on the table provided.
The third experiment is observing mitochondria in yeast/onion cells. We will be using the staining technique in order to obtain the result of the experiment. * Task 1: Respiration in Yeast

Materials:
* Beakers
* Pipettes
* Cuvettes
* 20% Glucose
* 20% Lactose
* 20% Sucrose
* 20% Maltose
* Distilled water
* Brom Thymol Blue (BTB)
* Spectrophotometer
* Measuring cylinders.
Procedures:
1. The spectrometer is set to 565nm. Distilled water is used to set the reading to the pure level. 2. 8mL of 20% glucose is placed in the beaker using a measuring cylinder. 3. 1ml of Brom Thymol Blue (BTB) is added into a respective tubes using a pipette. 4. 4ml from the mixture of Glucose and BTB taken and placed in test tube then added with 0.1ml of yeast extract. 5. The mixture then transferred into cuvette and placed into spectrophotometer. 6. The absorbance measured for 5 minutes. The reading taken within 30 seconds. 7. Steps 1-6 is repeated using 20% Lactose, 20% Sucrose, and 20% Maltose. 8. Reading obtained is recorded and compared with the others.

Results:
Time (s)| 20% Glucose| 20% Sucrose| 20% Maltose| 20% Lactose| 30| 1.053| 1.162| 1.323| 1.130|
60| 1.051| 1.161| 1.310| 1.123|
90| 1.049| 1.159| 1.304| 1.119|
120| 1.048| 1.159| 1.297| 1.116|
150| 1.045| 1.158| 1.295| 1.114|
180| 1.044| 1.155| 1.292| 1.111|
210| 1.041| 1.155| 1.289| 1.109|
240| 1.040| 1.154| 1.287| 1.107|
270| 1.037| 1.154| 1.287| 1.105|
300| 1.035| 1.154| 1.284| 1.103|

* Task 2: Respiratory Indicator
Materials:
* Test tubes
* Yeast extract
* 20% Glucose
* Water bath
* Parafilm
* Distilled water
* Tap water
* Methylene blue

Procedures:
1. 4 test tubes is obtained.
2. Each tube filled as table shown below,
Tube 1 (room temperature)| Tube 2 (100ºc)| Tube 3| Tube 4| 5ml yeast+1ml glucose+2ml methylene blue+2ml distilled water| 5ml yeast+1ml glucose+2ml methylene blue+2ml distilled water| 5ml water+1ml glucose+2ml methylene blue+2ml distilled water| 5ml yeast+1ml water+1ml methylene blue +2ml distilled water|

3. For tube 2, yeast is added and glucose is immersed the tube in water bath(100%) for 5 minutes. The, methylene blue is added. 4. Parafilm is used to cover all the tubes.
5. Initial time and color is recorded.
6. Time taken for the decolorisation to occur is recorded.

Result:

| Tube 1| Tube 2| Tube 3| Tube 4|
Observation| Dark blue(no change)| Dark blue(no change)| Dark blue(no change)| Dark blue(no change)|

* Task 3: Observing Mitochondrian of Onion Cells
Materials:
* Glass slides
* Sucrose solution
* Methylene blue
* Toothpick
* Onion cell
* Cover slip
* Microscope

Procedures:...
tracking img