Find the best tutors and institutes for Class 12 Tuition
Q12(a):
Discuss with your teacher and find out how to distinguish between (a) Plasmid DNA and Chromosomal DNA
Solution :
1. Definitions and Fundamental Nature
In prokaryotic organisms, such as Escherichia coli, the genetic material exists in two distinct forms: Chromosomal DNA and Plasmid DNA.
- Chromosomal DNA: It represents the primary genetic material, typically consisting of a single, large, circular molecule [Per the nucleoid model]. It contains the essential genes required for the survival, metabolism, and reproduction of the organism.
- Plasmid DNA: These are extrachromosomal, small, circular, double-stranded DNA molecules [Per the definition by Lederberg, 1952]. They replicate independently of the chromosomal DNA and carry non-essential, yet often advantageous, accessory genes (e.g., antibiotic resistance genes).
2. Comparative Analysis Table
| Feature | Chromosomal DNA | Plasmid DNA |
|---|---|---|
| Size | Extremely large (several million base pairs). | Small (1,000 to 200,000 base pairs). |
| Function | Encodes essential housekeeping proteins. | Encodes accessory traits (e.g., virulence, antibiotic resistance). |
| Replication | Synchronized with the cell cycle (once per division). | Autonomous replication (independent of the cell cycle). |
| Copy Number | Typically 1 per cell. | Variable (can be 1 to several hundred per cell). |
3. Analytical Differentiation via Gel Electrophoresis
To distinguish these molecules experimentally, one utilizes Agarose Gel Electrophoresis, based on the principle of size-dependent migration through a porous matrix [By Faraday's Laws of Electrophoresis].
4. Sequential Laboratory Procedure
- Cell Lysis: Disrupt the cell wall/membrane using SDS and lysozyme to release the total DNA content.
- Extraction: Use phenol-chloroform extraction to isolate total DNA from proteins and lipids.
- Gel Loading: Apply an electrical field across an agarose gel matrix.
- Observation:
- The large Chromosomal DNA remains trapped near the loading well due to its large molecular weight and restricted migration speed.
- The smaller Plasmid DNA migrates rapidly toward the anode (+ electrode), appearing as distinct, sharp bands in the lower region of the gel.
Final Solution: Chromosomal DNA and Plasmid DNA are distinguished by size, replication autonomy, and gene essentiality; experimentally, they are separated by agarose gel electrophoresis, where Chromosomal DNA remains near the loading well and Plasmid DNA migrates significantly further due to a smaller molecular weight.
More Questions from Class 12 Biology Biotechnology: Principles and Processes EXERCISES
- Q1: Can you list 10 recombinant proteins which are used in medical practice? Find out where they are used as therapeutics (use the internet).
- Q1: Can you list 10 recombinant proteins which are used in medical practice? Find out where they are used as therapeutics (use the internet).
- Q2: Make a chart (with diagrammatic representation) showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and the product it produces.
- Q2: Make a chart (with diagrammatic representation) showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and the product it produces.
- Q3: From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size? How did you know?
- Q3: From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size? How did you know?
- Q4: What would be the molar concentration of human DNA in a human cell? Consult your teacher.
- Q4: What would be the molar concentration of human DNA in a human cell? Consult your teacher.
- Q5: Do eukaryotic cells have restriction endonucleases? Justify your answer.
- Q5: Do eukaryotic cells have restriction endonucleases? Justify your answer.
- Q6: Besides better aeration and mixing properties, what other advantages do stirred tank bioreactors have over shake flasks?
- Q6: Besides better aeration and mixing properties, what other advantages do stirred tank bioreactors have over shake flasks?
- Q7: Collect 5 examples of palindromic DNA sequences by consulting your teacher. Better try to create a palindromic sequence by following base-pair rules.
- Q7: Collect 5 examples of palindromic DNA sequences by consulting your teacher. Better try to create a palindromic sequence by following base-pair rules.
- Q8: Can you recall meiosis and indicate at what stage a recombinant DNA is made?
- Q8: Can you recall meiosis and indicate at what stage a recombinant DNA is made?
- Q9: Can you think and answer how a reporter enzyme can be used to monitor transformation of host cells by foreign DNA in addition to a selectable marker?
- Q9: Can you think and answer how a reporter enzyme can be used to monitor transformation of host cells by foreign DNA in addition to a selectable marker?
- Q10(a): Describe briefly the following: (a) Origin of replication
- Q10(a): Describe briefly the following: (a) Origin of replication
- Q10(b): Describe briefly the following: (b) Bioreactors
- Q10(b): Describe briefly the following: (b) Bioreactors
- Q10(c): Describe briefly the following: (c) Downstream processing
- Q10(c): Describe briefly the following: (c) Downstream processing
- Q11(a): Explain briefly (a) PCR
- Q11(a): Explain briefly (a) PCR
- Q11(b): Explain briefly (b) Restriction enzymes and DNA
- Q11(b): Explain briefly (b) Restriction enzymes and DNA
- Q11(c): Explain briefly (c) Chitinase
- Q11(c): Explain briefly (c) Chitinase
- Q12(a): Discuss with your teacher and find out how to distinguish between (a) Plasmid DNA and Chromosomal DNA
- Q12(b): Discuss with your teacher and find out how to distinguish between (b) RNA and DNA
- Q12(b): Discuss with your teacher and find out how to distinguish between (b) RNA and DNA
- Q12(c): Discuss with your teacher and find out how to distinguish between (c) Exonuclease and Endonuclease
- Q12(c): Discuss with your teacher and find out how to distinguish between (c) Exonuclease and Endonuclease
CBSE Solutions for Class 12 Biology Biotechnology: Principles and Processes
Chapters in CBSE - Class 12 Biology
- Reproduction in Organisms
- Human Reproduction
- Reproductive Health
- Principles of Inheritance and Variation
- Molecular Basis of Inheritance
- Evolution
- Human Health and Disease
- Strategies for Enhancement in Food Production
- Microbes in Human Welfare
- Biotechnology and Its Applications
- Organisms and Populations
- Ecosystem
- Biodiversity and Conservation
- Environmental Issues
Top Tutors who teach Biotechnology: Principles and Processes
Top Tutor
Tollygunge, Kolkata
5 yrs of
Exp
3 students
38 hrs of classes completed
800
per hour
Online Classes
I have been giving tuitions to Class 12 students since October 2015. I was then in 2nd year of BSc Physics from the renowned 200 years old university, Presidency University. In total I taught 2 Class 12 students in Kolkata and 9 Class 12 students in Delhi. Currently I am teaching a Class 11 student from JNU Quarters Maths, Physics and Chemistry via Zoom app. I have whiteboard, colourful pens and other requirements to ease the teaching in a great way.
He has great ability to teach students by making intricate concept clear.he is also very honest.he gives full attention to me and never made me feel uncomfortable during the class.
Top Tutor
Maan, Pimpri-Chinchwad
10 yrs of
Exp
6 students
263 hrs of classes completed
1200
per hour
Online Classes
Student's Home
Tutor's home
I have been teaching students for the past 10 years and have guided many to students in getting excellent results, showcasing their best performance. Concept-based teaching and an extra emphasis on every student needs has helped me provide a quality teaching environment to my students.
Top Tutor
Edapally, Kochi
4 yrs of
Exp
48 hrs of classes completed
500
per hour
Student's Home
Tutor's home
Qualified french teacher and tutor with a master degree in french from delhi university. Working as a language expert in ernst and young. Qualified. Have 4 years of teaching experience. With c1 certification.
Top Tutor
Sector 92, Gurgaon
20 yrs of
Exp
2 students
1392 hrs of classes completed
1200
per hour
Online Classes
Student's Home
Tutor's home
I am teaching class 12th since last 23 years
My sin started mathematics tuition one month back and he very much improved. You had a Very good experience.
Top Tutor
Gharoli Gharoli, Delhi
16 yrs of
Exp
1 student
199 hrs of classes completed
600
per hour
Online Classes
Tutor's home
I bring with me 17 years of diverse experience in the pharmaceutical industry along with academic expertise, combining strong practical knowledge with a passion for teaching. I am dedicated to simplifying complex concepts and delivering them in an engaging manner, ensuring that students not only gain subject knowledge but also develop the skills, confidence, and potential required to achieve academic excellence and become industry-ready professionals.
Good tech and good behavior and good teaching style and full topic clear and all of best teacher and my side to best teacher.
Other Subjects in CBSE - Class 12
Download free CBSE - Class 12 Biology Biotechnology: Principles and Processes EXERCISES worksheets
Download Now
