Biochem Lab Quiz Pt. 2

Question 1

Carbohydrates such as starch are detected by mixing

Answer 1

2-4 drops of Lugol’s solution or iodine

Question 2

if starch is present

Answer 2

yellow brown to purple color

Question 3

positive result in test for complex carbohydrates

Answer 3

dark blue/black

Question 4

negative results in test for complex caebohydrates

Answer 4

reddish orange

Question 5

the presence of smaller carbohydrates like glucose can be determined by using

Answer 5

Benedict’s solution

Question 6

has copper ions with a light blue color

Answer 6

Benedict’s solution

Question 7

Negative result in Test for Reducing Simple Sugars

Answer 7

light blue

Question 8

color if there is low concentration of simple sugars in test for reducing simple sugars

Answer 8

light green

Question 9

color if there is high concentration of simple sugars in test for reducing simple sugars

Answer 9

yellow to orange brown

Question 10

the presence of proteins may be determined by mixing a solution with

Answer 10

Biuret Test solution

Question 11

Negative biuret test results

Answer 11

light blue/blue

Question 12

positive biuret test results

Answer 12

purple

Question 13

used for determining the presence of nucleic acids

Answer 13

(Dische) Diphenylamine test

Question 14

positive diphenylamine test results

Answer 14

blue

Question 15

negative diphenylamine test results

Answer 15

clear color

Question 16

if there is presence of RNA

Answer 16

green

Question 17

Test for Protein

Answer 17

Biuret Test

Question 18

5 drops of suspension
5 drops of 10% NaOH (sodium hydroxide)
5 drops of 0.5 cupric sulfate solution (CuSO4)

Answer 18

Biuret Test

Question 19

Test for Carbohydrates

Answer 19

Molisch Test

Question 20

10 drops of suspension
3 drops of Molisch reagent
8 drops of concentrated sulfuric acid (H2SO4)

Answer 20

Molisch Test

Question 21

2 mL of 1 M NaCl solution
2 mL of suspension
ethyl alcohol

Answer 21

isolation of nucleic acids

Question 22

Test for presence of DNA

Answer 22

Dische test

Question 23

5 drops cell suspension
5 drops diphenylamine
6 drops concentrated sulfuric acid
broken porcelain

Answer 23

Dische Test

Question 24

test for presence of RNA

Answer 24

Orcinol Test

Question 25

7 drops of Orcinol reagent
7 drops cell suspension

Answer 25

Orcinol Test

Question 26

general test for caebohydrates

Answer 26

Molisch’s Test

Question 27

Positive Molisch test

Answer 27

purple color complex

Question 28

Negative Molisch Test

Answer 28

no purple color

Question 29

specific test for reducing sugars or presence of free or potential aldehydes

Answer 29

Benedict’s Test

Question 30

No color change (Remains Blue) reducing sugars are absent

Answer 30

negative benedict’s test

Question 31

Formation of a reddish precipitate within three minutes. Reducing sugars are present

Answer 31

Positive Benedict’s Test

Question 32

used to distinguish between monosaccharides and disaccharides

Answer 32

Barfoed’s Test

Question 33

presence of littke dark red precipitate within 2-3 minutes

Answer 33

monosaccharide

Question 34

if no presence of little dark red precipitate

Answer 34

disaccharide

Question 35

development of brick red color within 3-5 minutes

Answer 35

Positive Barfoed’s Test

Question 36

absence of red color

Answer 36

Negative Barfoed’s test

Question 37

specific for ketones

Answer 37

Seliwanoff’s Test

Question 38

test for pentoses and nucleotides containing pentose sugars

Answer 38

Bial’s Test

Question 39

1 mL portions of test solutions
2 drops of Molisch’s reagent
0.5 mL of concentrated H2SO4

Answer 39

Molisch Test

Question 40

1 mL portions of test solutions
1.5 mL Benedict’s solution

Answer 40

Benedict’s Test

Question 41

1 mL portions of test solutions
1.5 mL Barfoed’s reagent

Answer 41

Barfoed’s Test

Question 42

1 mL portions of test solutions
1.5 mL Seliwanoff’s reagent

Answer 42

Seliwanoff’s test

Question 43

1 mL portions of test solutions
1 mL Bial’s reagent
1 mL pentanol

Answer 43

Bial’s test