Experiments

Question 1

To investigate the factors necessary for germination

Answer 1

Question 2

To investigate the digestive activity of a seed during germination

Answer 2

Question 3

To investigate the growth of leaf yeast on agar plates

Answer 3

Question 4

To investigate the influence of light intensity on the rate of photosynthesis

Question 5

Test for the presence of starch

Answer 5

add a few drops of iodine solution to the food sample
starch solution turns from yellow brown to , blue black

Question 6

to investigate the effect of Ph on the rate of catalyst activity

Answer 6

1. Add catalase , pH9 and washing up liquid to a garduated cylinder
2. add hydrogen peroxide to a boiling tube
3. place the boiling tube and graduated cylinder in a water bath of 25 degrees
4. take both out
5. slowly add hydrogen peroxide down side of graduated cylinder
6. calculate height of foam = the rate of enzyme activity
7. record initial volume and final volume after 2 mins
8. repeat for PH 4,7,10

Question 7

To investigate the effect of temperature on the rate of catalase activity

Question 8

To investigate the effect of temperature on the rate of catalase activity

Answer 8

1. Add catalase , pH9 and washing up liquid to a garduated cylinder
2. add hydrogen peroxide to a boiling tube
3. Stand the graduated cylinder and boiling tube in a water bath of 0 degrees
4. Slowly add ice cold hydrogen peroxide down side of graduated cylinder
5. Calculate height of foam
6. Record initial and final volume after 2 mins
7. repeat procedure for 25 degrees 40 and 60
8. record results

Question 9

Investigate the effect of heat denaturation on the activity of catalase

Answer 9

1. place the catalase in a boiling tube and place in water bath of 100 degrees
2. Add the boiled catalase , pH9 and washing up liquid to a graduated cylinder
3. Place both boiling tube and graduated cylinder in water bath of 25 degrees
4. slowly add ice cold hydrogen peroxide down the side of the graduated cylinder
5. calculate height of foam
6. record initial and final volume of foam
7. repeat procedure with unboiled catalase
8. Record results

Question 10

Prepare one enzyme immobilisation

Answer 10

1. Mix sodium alginate and water and yeast which contains the enzyme sucrase
2. draw the mixture into a syringe
3. release the mixture into syringe , one drop at a time , into calcium chloride solution
4. beads containing sucrase will form
5. leave the beads to harden for 15 mins
6. Filter the beads through a sieve and rinse with distilled water to remove any excess free yeast on the outside of the beads

Question 11

Investigate the influence of light intensity on the rate of photosynthesis

Question 12

Prepare and show the production of alcohol by yeast

Question 13

Conduct any activity to demonstrate osmosis

Question 14

Examine the application of enzyme immobilisation

Answer 14

1. Mix water and yeast and pour into separate funnel( free yeast control )
2. Place the beads into another separating funnel (immobilised yeast )
3. pour sucrose ( substrate ) solution into each funnel
4. using clinistix , immediately test samples frome each funnel for glucose
5. repeat the test in 2 min intervals until glucose appears for both
6. compare the turbidity of solutions from both funnels
7. if glucose is present , the end of the strip will turn purple
8. Record result