experiments Flashcards
what is the substrate for immobilized enzymes
sucrose
what is the enzyme used for immobilized enzymes
sucrase found in yeast
what is the product of the immobilized enzyme experiment
glucose
how did you immobilize enzymes
Using a syringe, we slowly dropped sodium alginate and yeast into calcium chloride solution.
Beads of calcium alginate gel formed immobilizing the yeast cells and sucrase enzyme. We
then allowed the beads to harden for 15 minutes.
how did you test for glucose
Using glucose clinistix. Positive test showed purple.
Any differences in the product formed between immobilized and free sucrase?:
Glucose in both. In free yeast, product was cloudy due to yeast being present along with glucose. In
immobilized yeast,, product was clear as yeast was immobilized in calcium alginate gel in separating
funnel.
Results of immobilised enzymes
Glucose present in both. Produced more quickly in free yeast. Free yeast product was cloudy.
Immobilized yeast product was clear
what is the substrate for the effect of heat on enzymes
hydrogen peroxide
what is the enzyme for the effect of heat on enzymes
catalase (found in celery)
what is product for the effect of heat on enzymes
oxygen and water
Why using pH buffer 9 for the effect of heat on enzymes
optimal pH for catalase enzyme to work
Why keep temperature constant at 25 – 30oC for the effect of heat on enzymes
This is optimal temperature for catalase
enzyme
How did we denature catalase for the effect of heat on enzymes
boiling. Active site changed shape, enzyme is denatured.
How will we know if enzyme is breaking down hydrogen peroxide for the effect of heat on enzymes
oxygen and water
(foam) will be produced
How will we know if enzyme is not working for the effect of heat on enzymes
no oxygen and water (foam) will be
produced (products)
Why washing up liquid for the effect of heat on enzymes
traps water as foam so we can quantify the product
to test for reducing sugars?
Benedicts solution
to test for protein
biuret solution
to test for fats
brown paper test
to test for starch
iodine
what is a positive result for reducing sugar
solution will turn red
what is a positive result for protein and what is a negative result
positive = purple
negative = blue
what is a positive test for starch
dark blue black colour
what is biuret solution
sodium hydroxide , copper sulfate and
describe the steps of reducing sugar
put 5% glucose into 100ml of water and benedict solution and place it in a test tube in a different test tube add water and benedict solution and heat both test tubes do not boil
describe the test for protein
dissolve protein in water then add sodium hydroxide add a few drops of copper sulfate in a different test tube do the same thing without protein
name a substance that can be used to make ethanol
glucose or starch
what substance other than ethanol is produced
co2
what was the control for the making of ethanol experiment
Same apparatus but with no yeast or boiled
how did you know when fermentation was finished
No more bubbles given off
how did you test for alchohol
Idoform test - Potassium iodide & sodium hypochlrorite
what is a positive result for the iodoform test
yellow crystals
what is a qualitative analysis
looking for the presence or absence of organisms using a key to identify the flora and fauna
how did you do a quantitative study
by randomly throwing a quantrant
what is a quantitive study
the precentage of an organism in a small area
