Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

a level biology > required practicals > Flashcards

required practicals Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

what is the test for starch ?

A

iodine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how do you carry out iodine test ?

A
  • add 1cm of sample to a dimple in spotting tile
  • add a few drops of iodine to solution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the positive test result for the iodine test ?

A

blue/black colour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the test for lipids ?

A

emulsion test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how do you carry out the emulsion test ?

A
  • add 1 cm ethanol to a test tube
  • add 1cm sample
  • shake vigorously to dissolve
  • add 1cm of cold water
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the positive result for the emulsion test ?

A

cloudy emulsion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the test for proteins ?

A

biuret test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how do you carry out the biuret test ?

A
  • add 2cm sample solution to test tube
  • add 2cm Biuret solution
  • observe colour change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the positive result for the biuret test ?

A

lilac colour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the test for reducing sugars ?

A

benedict’s test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how do you carry out the benedict’s test ?

A
  • add 2cm sample solution to test tube
  • add 2cm to benedict’s reagent
  • heat gently in a water bath at 85 degrees for 2 mins
  • observe colour change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the positive result for benedict’s test ?

A

green/yellow/brick red colour or precipitate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the test for non reducing sugars ?

A

modified benedict’s test - acid hydrolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how do you carry out acid hydrolysis for non reducing sugars ?

A
  • add 2cm sample solution to test tube
  • add 1cm of 1m HCL
  • boil in water bath for 1 min
  • neutralize with NaHCO3 powder
  • check pH with indicator paper
  • carry out normal benedict’s test
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the positive result for the modified benedict’s test ?

A

green/red colour or brick red precipitate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the colour for a negative result in the starch test ?

A

brown/ yellow coloured solution

17
Q

what is the negative result for the emulsion test ?

A

colourless solution

18
Q

what is the negative test result for the biuret test, reducing sugars test and non reducing sugars test ?

A

blue solution

19
Q

what is the uncertainty value of the 10cm 3 measuring cylinder ?

A

value of smallest division/2

a level biology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions