experiments

Question 1

what is the substrate for immobilized enzymes

Answer 1

sucrose

Question 2

what is the enzyme used for immobilized enzymes

Answer 2

sucrase found in yeast

Question 3

what is the product of the immobilized enzyme experiment

Answer 3

glucose

Question 4

how did you immobilize enzymes

Answer 4

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.

Question 5

how did you test for glucose

Answer 5

Using glucose clinistix. Positive test showed purple.

Question 6

Any differences in the product formed between immobilized and free sucrase?:

Answer 6

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.

Question 7

Results of immobilised enzymes

Answer 7

Glucose present in both. Produced more quickly in free yeast. Free yeast product was cloudy.
Immobilized yeast product was clear

Question 8

what is the substrate for the effect of heat on enzymes

Answer 8

hydrogen peroxide

Question 9

what is the enzyme for the effect of heat on enzymes

Answer 9

catalase (found in celery)

Question 10

what is product for the effect of heat on enzymes

Answer 10

oxygen and water

Question 11

Why using pH buffer 9 for the effect of heat on enzymes

Answer 11

optimal pH for catalase enzyme to work

Question 12

Why keep temperature constant at 25 – 30oC for the effect of heat on enzymes

Answer 12

This is optimal temperature for catalase
enzyme

Question 13

How did we denature catalase for the effect of heat on enzymes

Answer 13

boiling. Active site changed shape, enzyme is denatured.

Question 14

How will we know if enzyme is breaking down hydrogen peroxide for the effect of heat on enzymes

Answer 14

oxygen and water
(foam) will be produced

Question 15

How will we know if enzyme is not working for the effect of heat on enzymes

Answer 15

no oxygen and water (foam) will be
produced (products)

Question 16

Why washing up liquid for the effect of heat on enzymes

Answer 16

traps water as foam so we can quantify the product

Question 17

to test for reducing sugars?

Answer 17

Benedicts solution

Question 18

to test for protein

Answer 18

biuret solution

Question 19

to test for fats

Answer 19

brown paper test

Question 20

to test for starch

Answer 20

iodine

Question 21

what is a positive result for reducing sugar

Answer 21

solution will turn red

Question 22

what is a positive result for protein and what is a negative result

Answer 22

positive = purple
negative = blue

Question 23

what is a positive test for starch

Answer 23

dark blue black colour

Question 24

what is biuret solution

Answer 24

sodium hydroxide , copper sulfate and

Question 25

describe the steps of reducing sugar

Answer 25

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

Question 26

describe the test for protein

Answer 26

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

Question 27

name a substance that can be used to make ethanol

Answer 27

glucose or starch

Question 28

what substance other than ethanol is produced

Answer 28

co2

Question 29

what was the control for the making of ethanol experiment

Answer 29

Same apparatus but with no yeast or boiled

Question 30

how did you know when fermentation was finished

Answer 30

No more bubbles given off

Question 31

how did you test for alchohol

Answer 31

Idoform test - Potassium iodide & sodium hypochlrorite

Question 32

what is a positive result for the iodoform test

Answer 32

yellow crystals

Question 33

what is a qualitative analysis

Answer 33

looking for the presence or absence of organisms using a key to identify the flora and fauna

Question 34

how did you do a quantitative study

Answer 34

by randomly throwing a quantrant

Question 35

what is a quantitive study

Answer 35

the precentage of an organism in a small area