JEE (Based on NTA Guidelines-IIT Engg.) Mains Chemistry Coaching Programs
πΉ Video Course 2024 (0 Lectures [0 Mins]): Offline Support
Click Here to View & Get Complete Material
Rs. 100.00
1 Month Validity (Multiple Devices)
β³ π― Online Tests (1 Tests [30 Questions Each]): NTA Pattern, Analytics & Explanations
Click Here to View & Get Complete Material
Rs. 100.00
3 Year Validity (Multiple Devices)
π Study Material (159 Notes): 2024-2025 Syllabus
Click Here to View & Get Complete Material
Rs. 350.00
3 Year Validity (Multiple Devices)
π― 144 Numeric, 2994 MCQs (& PYQs) with Full Explanations (2024-2025 Exam)
Click Here to View & Get Complete Material
Rs. 650.00
3 Year Validity (Multiple Devices)
Biology Class 12 NCERT Solutions: Chapter 11 Biotechnology: Principles and Processes Part 2
Q.5 Do eukaryotic cells have restriction endonucleases? Justify your answer.
Answer:
- No, eukaryotic cells do not have restriction endonucleases. This is because the DNA of eukaryotes is highly methylated by a modified enzyme, called methylase.
- Methylation protects the DNA from the activity of restriction enzymes.
- These enzymes are present in prokaryotic cells where they help prevent the invasion of DNA by virus.
Q.6 Besides better aeration and mixing properties what other advantages do stirred tank bioreactors have over shake flasks?
Answer:
- The shake flask method is used for a small-scale production of biotechnological products in a laboratory.
- Whereas stirred tank bioreactors are used for a large-scale production of biotechnology products.
- Stirred tank bioreactors have several advantages over shake flasks:
(i) Small volumes of culture can be taken out from the reactor for testing.
(ii) It has a foam breaker for regulating the foam.
(iii) It has a control system that regulates the temperature and .
Q.7 Collect 5 examples of palindromic DNA sequences by consulting your teacher. Better try to create a palindromic sequence by following base-pair rules.
Answer:
- The palindromic sequence is a certain sequence of the DNA that reads the same whether read from 5Υ 3 βdirection or from 3β 5Υ direction.
- They are the site for the action of restriction enzymes. Most restriction enzymes are palindromic sequences.
- Five examples of palindromic sequences are-
(i) 5 β-AGCT-3β
3 β-TCGA-5β
(ii) 5 β-GAATTC-3β
3 β-CTTAAG-5β
(iii) 5 β-AAGCTT-3β
3 β-TTCGAA-5β
(iv) 5 β-GTCGAC-3β
3 β-CAGCTG-5β
(v) 5 β-CTGCAG-3β
3 β-GACGTC-5β