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39 questions in this collection · Page 3 of 4
Biotechnology Principles And Processes
Biotechnology Principles And Processes
AI-generated explanation. Check against your textbook.
Explanation:The wrong statement is option 1. Restriction enzymes do not inspect the length of a DNA sequence; they recognize and cut at specific short, usually palindromic, nucleotide sequences. The site is defined by its sequence, not by a general length check. Options 2, 3, and 4 are correct: restriction enzymes cut at palindromic sites; they are useful in genetic engineering; and DNA ligases can join sticky ends created by these enzymes.
🧠 Did You Know?Restriction enzymes generate either sticky (overhang) or blunt ends, which are used to ligate DNA fragments in genetic engineering.
💡 NCERT Memory Line:Restriction enzymes cut DNA at specific palindromic sequences, enabling precise gene manipulation in biotechnology.
Biotechnology Principles And Processes
| Column-I | Column-II |
|---|---|
| (A)Bt cotton | (I)Gene therapy |
| (B)Adenosine deaminase deficiency | (II)Cellular defence |
| (C)RNAi | (III)Detection of HIV infection |
| (D)PCR | (IV)Bacillus thuringiensis |
Biotechnology Principles And Processes
AI-generated explanation. Check against your textbook.
Explanation:In gel electrophoresis, DNA fragments are stained with ethidium bromide and then viewed under ultraviolet (UV) light. Ethidium bromide intercalates between DNA bases and fluoresces, making the DNA bands visible. This is described in NCERT as a standard method for visualization.
🧠 Did You Know?Ethidium bromide emits orange fluorescence when bound to DNA and exposed to UV light, revealing band patterns that correspond to fragment sizes.
💡 NCERT Memory Line:DNA is stained with a DNA-specific dye (ethidium bromide) and visualized under UV light to see gel bands.
Biotechnology Principles And Processes
AI-generated explanation. Check against your textbook.
Explanation:Spooling refers to gathering or collecting the isolated DNA strands after extraction, i.e., the DNA that has been purified is spooled around a rod or stick. This is the collection step of DNA isolation. Hence, option 4 is correct.
🧠 Did You Know?In labs, DNA can appear as a white, cottony mass that can be wound or spooled on a glass rod when it precipitates out of solution.
💡 NCERT Memory Line:Spooling = collection of isolated DNA during isolation procedures.
Biotechnology Principles And Processes
Biotechnology Principles And Processes
AI-generated explanation. Check against your textbook.
Explanation:The incorrect statement is option 1. Restriction endonucleases cut both strands of DNA at specific sites, producing double-stranded breaks (blunt or with sticky ends). They recognize specific palindromic sequences and cut within those sites, breaking the sugar-phosphate backbone on both strands. Options 2, 3, and 4 correctly describe these features as per NCERT biology.
🧠 Did You Know?Restriction enzymes are essential tools in genetic engineering and cloning, enabling precise cutting and joining of DNA fragments.
💡 NCERT Memory Line:Restriction endonucleases recognize palindromic DNA sequences and make double-stranded cuts at specific sites.
Biotechnology Principles And Processes
Biotechnology Principles And Processes
Biotechnology Principles And Processes