This set of Enzyme Technology Multiple Choice Questions & Answers (MCQs) focuses on “Extraction of Enzymes by Chemical Methods – 1”.
1. Which of the following is not a technique for the extraction of enzymes by chemical methods?
a) Alkali treatment
b) Osmotic shock
c) Detergent treatment
d) Homogenization
View Answer
Explanation: Homogenization is a method to extract enzymes using physical methods. Chemical methods involve different chemicals like EDTA, lysozymes, NaoH etc. to isolate enzymes from selected sources. Hence alkali treatment, Osmotic shock and Detergent treatment falling into the category extracting enzymes by chemical methods.
2. In ________ treatment, produced basic radicals mediate a nucleophilic attack on compounds of cell wall on membrane leading to destabilization and fragmentation of membrane followed by release of enzymes.
a) EDTA
b) Osmotic shock
c) Alkali
d) Detergent
View Answer
Explanation: In alkali treatment, Alkalis produce basic radical which mediate a nucleophilic attack on compounds of cell wall or cell membrane which leads to destabilization of membrane, followed by membrane fragmentation. This allows leakage of cytoplasm which has enzyme of interest. Care has to be taken about alkalinity of the solution as enzyme may get denaturated at high pH.
3. ____________ is an enzyme, which is highly produced by egg white and lachrymal glands.
a) Amylases
b) Lysozyme
c) Invertase
d) Protease
View Answer
Explanation: Lysozyme is produced by egg white and lachrymal glands. Amylases is produced by malted barley, bacillus species, aspergillus species etc. Invertase is produced from saccharomyces species and protease from aspergillus and bacillus species.
4. Gram positive bacteria are highly susceptible to lysozyme treatment.
a) True
b) False
View Answer
Explanation: Lysozyme catalyzes the β (1 → 4) glycosidic linkages of NAM (N-acetyl muramic acid) and NAG (N-acetyl glucosamine) present in bacterial peptidoglycan. Peptidoglycan content in high in gram positive bacteria as compared to gram negative bacteria. Hence gram positive bacteria are highly susceptible lysozyme treatment.
5. In ___________ treatment, certain molecules interact through ionic or Vander wall forces which leads to solubilization of phospholipids and lipoprotein which in turn, increases membrane permeability directing to cell lysis.
a) Lysozyme
b) EDTA
c) Detergent
d) NaoH
View Answer
Explanation: In detergent treatment, Cell lysis is performed by increasing membrane permeability by solubilizing phospholipids and lipoproteins present in the cell wall. This is done through interaction if detergents through ionic or Vander wall forces. In lysozyme treatment, lysozymes act by catalyzing the β (1 → 4) glycosidic linkages of NAM and NAG present in the cell wall. EDTA acts as a divalent chelator and chelate ions present in the cell wall. NaOH is an alkali and act by having a nucleophilic attack on the cell wall or cell membrane.
6. Which of the following is cationic detergent?
a) Sodium dodecyl sulphate (SDS)
b) Cetyl triethyl ammonium bromide
c) Sodium lauryl sulphate (SLS)
d) Triton-X-100
View Answer
Explanation: In detergent treatment, 2 types of detergent are used namely, ionic and non-ionic. Ionic also has 2 types: cationic and anionic detergents. SDS and SLS and anionic detergents as compared to triton-X-100 which is a non-ionic detergent. Cetyl trimethyl ammonium bromide is a cationic detergent.
7. __________________ is an example of anionic detergent.
a) Tween
b) Cetyl triethyl ammonium bromide
c) Sodium dodecyl sulphate (SDS)
d) Triton-X-100
View Answer
Explanation: SDS is an anionic detergent as compared to tween and triton-X-100 which are examples of non-ionic detergents. Cetyl triethyl ammonium bromide is an example for cationic detergents. Sodium lauryl sulphate is also an example for anionic detergents.
8. The techniques which adopts the hypertonic and hypotonic condition for cell lysis is referred to as ____________
a) EDTA treatment
b) Ultrasonification
c) Osmotic shock
d) Homogenization
View Answer
Explanation: Osmotic shock is a technique which utilizes the hypertonic and hypotonic condition for cell lysis. In hypertonic condition, water molecules move out due to osmosis and shrink the cell. Whereas in the hypotonic condition, the water molecules enter the cell, bulging the cytosol and finally bursting of cell to remove the cell content outside. 1.4 % buffered sucrose is used for this purpose. Ultrasonification and homogenization are methods to extract enzymes by physical methods. EDTA acts as a chelating agent and thus extract enzymes by chemical methods.
Sanfoundry Global Education & Learning Series – Enzyme Technology.
To practice all areas of Enzyme Technology, here is complete set of 1000+ Multiple Choice Questions and Answers.
If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]
- Check Biotechnology Books
- Practice Biotechnology MCQs
- Check Enzyme Technology Books
- Apply for Biotechnology Internship
- Check Chemical Engineering Books
