Digestive Enzymes Flashcards
Define enzyme:
catalyst that speeds up a chemical reaction
Two factors that can denature enzymes:
heat and extreme pH
In the digestive system, most of the foods we ingest are broken down by the process of:
hydrolysis
The enzymes that facilitate hydrolysis are collectively known as:
hydrolases
The enzyme that starts carbohydrate digestion is:
amylase
Carbohydrate digestion starts in the:
oral cavity
Amylase is released by the:
salivary glands
Which part of the small intestine is pancreatic amylase released into?
duodenum
The optimal pH for amylase is pH:
7
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.)
- Lugol’s IKI solution
- Benedict’s reagent
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.
Lugol’s IKI solution
If the IKI turns from brown to black, then starch is:
present
The brown color is considered a positive or negative result?
Lugol’s IKI solution
negative - no starch present
The black color is considered a positive or negative result?
Lugol’s IKI solution
positive - start is present
Used to test for reducing sugars:
Most of the disaccharides and the monosaccharides are reducing sugars - but not starch
Benedict’s reagent
Blue color indicates a positive or negative result?
Benedict’s reagent
negative
Green / orange / brown color indicates a positive or negative result?
(Benedict’s reagent)
positive
Protein digestion starts in the:
stomach
Protein digestion finishes in the:
small intestine
In order to be absorbed by the small intestine, proteins need to be broken down into:
amino acids
The enzyme produced by the stomach is:
pepsin
Pepsin requires a pH of
2
The enzyme trypsin is released by what gland?
pancreas
Trypsin requires a pH of
7
If BAPNA is undigested in solution, does it have color or is it colorless?
colorless / transparent
If the bond is chemically broken between BAPNA and the amino acid, does it have color or is it colorless?
color
solution turns from transparent/colorless to yellow
If the solution containing synthetic protein (BAPNA) is clear, this indicates:
- no amino acids
- negative result
If the solution containing synthetic protein (BAPNA) is yellow, this indicates:
- amino acids
- positive result
(the deeper the color change, the more product that is produced)
Most of triglyceride digestion occurs where?
small intestine
The enzyme lipase is produced by the:
pancreas
Lipase hydrolyzes triglycerides into:
monoglycerides and fatty acids
Which organ produces bile?
liver
Which organ stores and concentrates bile?
gallbladder
What is the purpose of bile salts?
emulsification of fats
In the triglyceride digestion experiment, we use cream in which:
powdered blue litmus has been added
Blue litmus paper will turn red if:
an acid is present
If the litmus cream (triglycerides) remain blue, this indicates:
- no change in pH
- negative result for presence of fatty acids
If the litmus cream (triglycerides turns to a purplish color, then to a red color, this indicates:
- lower pH (becomes acidic)
- positive result for fatty acids
What slows down chemical reactions?
ICE
What speeds up chemical reactions?
HEAT
