Digestive Enzymes

Question 1

Define enzyme:

Answer 1

catalyst that speeds up a chemical reaction

Question 2

Two factors that can denature enzymes:

Answer 2

heat and extreme pH

Question 3

In the digestive system, most of the foods we ingest are broken down by the process of:

Answer 3

hydrolysis

Question 4

The enzymes that facilitate hydrolysis are collectively known as:

Answer 4

hydrolases

Question 5

The enzyme that starts carbohydrate digestion is:

Answer 5

amylase

Question 6

Carbohydrate digestion starts in the:

Answer 6

oral cavity

Question 7

Amylase is released by the:

Answer 7

salivary glands

Question 8

Which part of the small intestine is pancreatic amylase released into?

Answer 8

duodenum

Question 9

The optimal pH for amylase is pH:

Answer 9

7

Question 10

There are two assays used to help analyze carbohydrate digestion:
(An assay is generally a test that indirectly shows that a chemical reaction has occured; In this case, we use a color change to indicate a particular result.)

Answer 10

• Lugol’s IKI solution

- Benedict’s reagent

Question 11

Used to test for the presence of starch. For this test, we use a spot plate. Put a drop of your solution in one of the wells. Add one drop of IKI.

Answer 11

Lugol’s IKI solution

Question 12

If the IKI turns from brown to black, then starch is:

Answer 12

present

Question 13

The brown color is considered a positive or negative result?

Lugol’s IKI solution

Answer 13

negative - no starch present

Question 14

The black color is considered a positive or negative result?

Lugol’s IKI solution

Answer 14

positive - start is present

Question 15

Used to test for reducing sugars:

Most of the disaccharides and the monosaccharides are reducing sugars - but not starch

Answer 15

Benedict’s reagent

Question 16

Blue color indicates a positive or negative result?

Benedict’s reagent

Answer 16

negative

Question 17

Green / orange / brown color indicates a positive or negative result?
(Benedict’s reagent)

Answer 17

positive

Question 18

Protein digestion starts in the:

Answer 18

stomach

Question 19

Protein digestion finishes in the:

Answer 19

small intestine

Question 20

In order to be absorbed by the small intestine, proteins need to be broken down into:

Answer 20

amino acids

Question 21

The enzyme produced by the stomach is:

Answer 21

pepsin

Question 22

Pepsin requires a pH of

Answer 22

2

Question 23

The enzyme trypsin is released by what gland?

Answer 23

pancreas

Question 24

Trypsin requires a pH of

Answer 24

7

Question 25

If BAPNA is undigested in solution, does it have color or is it colorless?

Answer 25

colorless / transparent

Question 26

If the bond is chemically broken between BAPNA and the amino acid, does it have color or is it colorless?

Answer 26

color

solution turns from transparent/colorless to yellow

Question 27

If the solution containing synthetic protein (BAPNA) is clear, this indicates:

Answer 27

• no amino acids

- negative result

Question 28

If the solution containing synthetic protein (BAPNA) is yellow, this indicates:

Answer 28

• amino acids
• positive result

(the deeper the color change, the more product that is produced)

Question 29

Most of triglyceride digestion occurs where?

Answer 29

small intestine

Question 30

The enzyme lipase is produced by the:

Answer 30

pancreas

Question 31

Lipase hydrolyzes triglycerides into:

Answer 31

monoglycerides and fatty acids

Question 32

Which organ produces bile?

Answer 32

liver

Question 33

Which organ stores and concentrates bile?

Answer 33

gallbladder

Question 34

What is the purpose of bile salts?

Answer 34

emulsification of fats

Question 35

In the triglyceride digestion experiment, we use cream in which:

Answer 35

powdered blue litmus has been added

Question 36

Blue litmus paper will turn red if:

Answer 36

an acid is present

Question 37

If the litmus cream (triglycerides) remain blue, this indicates:

Answer 37

• no change in pH

- negative result for presence of fatty acids

Question 38

If the litmus cream (triglycerides turns to a purplish color, then to a red color, this indicates:

Answer 38

• lower pH (becomes acidic)

- positive result for fatty acids

Question 39

What slows down chemical reactions?

Answer 39

ICE

Question 40

What speeds up chemical reactions?

Answer 40

HEAT