1. Phytanase can be extracted only from ___________ species.
a) plant
b) prokaryote
c) fungal
d) animal
Explanation: Prokaryotes and Fungal species have been identified to have industrially important enzymes like protease, lipase, cellulase etc. Lactase synthase, arginase can be extracted from animal species. Phytanase is only available in plant species in abundant. Hence phytanase is extracted from plant species.
2. Which of the following is not a reason for selected source to be used readily for the production of enzymes?
a) Socio-economical
b) Political
c) Extraction procedure
d) Geographical
Explanation: Extraction procedure is not the reason for the selected source to be used readily for the production of enzymes. The reasons for not using the selected source are socio-economical, political, geographical etc. Hence alternative modern approach has been used to boost enzyme level in a cell before extraction and it is called rDNA technology.
3. The technology wherein gene transfer to host organisms by vectors is referred to as ________
a) rDNA technology
b) extraction
c) isolation
d) purification
Explanation: The selected source may not be available for use due to various reasons. Thus, modern technology has been used to boost enzyme level in a cell before extraction. This can be done by using vector which will transfer gene of interest to host organisms. This procedure is called rDNA technology, Extraction, Isolation and Purification will come in later stages after rDNA technology has been done.
4. Enzymes which are secreted outside the body cells are referred to as ________ enzymes.
a) extracellular
b) intracellular
c) cytoplasmic
d) mitochondrial
Explanation: Enzyme location is an important factor during extraction. Some enzymes are secreted outside the body cells and called extracellular enzymes. Certain enzymes are located inside the body cells and are called intracellular enzymes. Enzymes located in cytoplasm and mitochondria and referred to as cytoplasmic and mitochondrial enzymes respectively.
5. Protease is an intracellular enzyme.
a) True
b) False
Explanation: Protease is an extracellular enzyme as the enzyme is located outside the body and hence it is an extracellular enzyme. Conjugating enzyme is highly concentrated in liver mitochondria which means it is located inside the cells. Hence it is an intracellular enzyme.
6. Which of the following should be implemented in case of extracting conjugating enzymes?
a) Apt chemical compounds
b) Suitable density gradient
c) Centrifugation technique
d) Proper filtration
Explanation: Conjugating enzymes are intracellular enzymes that are located in liver mitochondria. In order to avoid contamination from other proteins, we need to use a suitable density gradient which will remove unwanted debris. Apt chemical compounds, centrifugation and proper filtration can be used in case extracting extracellular enzyme as it is much easier to isolate.
7. 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
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.
8. 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
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.
9. ____________ is an enzyme, which is highly produced by egg white and lachrymal glands.
a) Amylases
b) Lysozyme
c) Invertase
d) Protease
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.
10. Gram positive bacteria are highly susceptible to lysozyme treatment.
a) True
b) false
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.