Post Lab

Question 1

Observation for Pineapple glass 3

Answer 1

Gelatin does not form liquid

Question 2

Observation for Pineapple glass 2

Answer 2

Gelatin breaks down and forms liquid

Question 3

Observation for Pineapple glass 1

Answer 3

No changes

Question 4

They are capable of hydrolyzing peptide bonds and are also referred to as peptidases, proteases or proteinases.

Answer 4

Proteolytic Enzymes

Question 5

Proteolytic Enzymes belongs to the hydrolase class of enzymes (T/F)

Answer 5

True (Hydrolase)

Question 6

Action of Proteolytic is essential to:

Answer 6

Digestion
Protein Turnover
Cell Division
Blood-clotting cascade
Signal Transduction

Question 7

Generic name given to the set of derived
endopeptidases belonging to members of the Bromeliaceae family, being able to break the peptide bond, separating proteins and amino acids

Answer 7

Bromelain

Question 8

Scientific name of Pineapple

Answer 8

Ananas comosus

Question 9

Optimum Temperature and pH of enzyme
bromelain

Answer 9

50 C
pH 7.0

Question 10

Egg albumin solution Observation

Answer 10

Firm liquid

Question 11

Beaten egg whites Observation

Answer 11

Bubble formation

Question 12

Heated egg whites Observation

Answer 12

Solidifies

Question 13

Egg albumin solution, alcohol Observation

Answer 13

Solidifies

Question 14

Egg albumin solution and vinegar Observation

Answer 14

Solidifies

Question 15

Refers to the physical changes that take place in a protein exposed to abnormal conditions in the environment.

Answer 15

Protein Denaturation

Question 16

Causes of Protein Denarturation

Answer 16

Heat (Temperature)
Acid
Alcohol
Mechanical Agitation
High Salt Concentration

Question 17

When a protein denatures, its complicated folded structure _______, and it becomes just a __________ of amino acids again.

Answer 17

Unravels
Long strand

Question 18

What Protein structures do weak chemical forces hold

Answer 18

Tertiary Protein Structures
Secondary Protein Structures

Question 19

It is dependent of its shape, so denatured proteins are no longer functional.

Answer 19

Protein Function

Question 20

During cooking the applied heat causes proteins to ________

Answer 20

Vibrate

Question 21

This destroys the weak bonds holding proteins in their complex shape

Answer 21

Applied (Heat)

Question 22

The unraveled protein strands then stick together, forming an

Answer 22

Aggregate (or network)

Question 23

What is biuret reagent made of

Answer 23

Copper sulfate CuSO4 (Strong base)

Question 24

Test for peptide bonds

Answer 24

Biuret’s Test

Question 25

Positive result for Biuret Test

Answer 25

Albumin – violet Peptone – violet Gelatin – violet Casein – violet Amino Acids – blue

Question 26

How many peptide bonds are required for the formation of violet complex?

Answer 26

Two peptide bonds are at least required

Question 27

Ninhydrin Reacts with ______-

Answer 27

Alpha - Amino acids (--NH2)

Question 28

Color given by Ninhydrin when it reacts with α-amino acids

Answer 28

purple colored complex

Question 29

In Ninhydrin, Tyrosine and Tryptophan results in a purple color meaning they are?

Answer 29

α-amino acids

Question 30

Ninhydrin positive result for Proline and Hydroxyproline

Answer 30

yellow

Question 31

Test used to detect amino acids containing an aromatic nucleus

Answer 31

Xanthoproteic Test

Question 32

Positive color result for Xanthoproteic test

Answer 32

Tyrosine - Yellow Tryptophan - Yellow Phenylalanine - Yellow

Question 33

It is the only amino acid containing a phenol group

Answer 33

Tyrosine

Question 34

It is a hydroxyl group attached to a benzene ring

Answer 34

Phenol group

Question 35

Test specific for tyrosine, the only amino acid containing a phenol group,

Answer 35

Millon’s Test

Question 36

Positive color result for tyrosine

Answer 36

Tyrosine - Brick Red Phenol Solution - Brick Red

Question 37

specific for free Arginine or proteins containing Arginine

Answer 37

Sakaguchi Test

Question 38

Arginine belongs to what group?

Answer 38

Guanidine group

Question 39

Positive color result for Sakaguchi test

Answer 39

red-coloured complex

Question 40

Specific for Tryptophan in proteins

Answer 40

Hopkins-Cole Test

Question 41

Sulphuric acid in presence of mercuric sulphate oxidizes the _________ of tryptophan

Answer 41

Indole nucleus

Question 42

Positive result for Hopkins-Cole Test

Answer 42

violet-purple colored complex