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A low level of expression of lac operon ...

A low level of expression of lac operon occurs at all the time. Can you explain the logic behind this phenomenon?

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In the complete absence of expression of lac operon, permease will not be synthesised which is essential for transport of lactose from medium into the cells. And if lactose cannot be transported into the cell, then it cannot act as inducers hence, cannot relieve the lac operon from its repressed state. During translation, if the codon on mRNA is AUG, then
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OSWAAL PUBLICATION-MOLECULAR BASIS OF INHERITANCE -TOPIC-2: Short Answer Type Question- I
  1. Differentiate between sense and antisense strands of DNA.

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  2. A single base mutation in a gene may not 'always' result in loss or ga...

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  3. A low level of expression of lac operon occurs at all the time. Can yo...

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  4. What are the functions of (i) methylated guanasine cap, (ii) poly-A"ta...

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  5. Comment on the utility of variability in number of tandem repeats duri...

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  6. Give an account of mRNA.

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  7. Differentiate between Exons and Introns.

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  8. How is a polypeptide chain synthesis terminated during protein synthes...

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  9. What are structural genes? Name the three structural genes present in ...

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  10. What do you understand by UTR ? Mention its role in translation.

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  11. Enumerate the goals of human genome project.

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  12. Three codons on mRNA are not recognized by transfer RNA. What are they...

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  13. Why is it essential that tRNA binds to both an amino acid and an mRNA ...

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  14. What will these DNA codons be translated into TAC, AAA, ATC? (b) Wh...

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  15. Two petitioner fathers filed case against a lady claiming to be the fa...

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  16. Draw the structure of the initiator tRNA adaptor molecule.

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  17. Why is tRNA called an adaptor molecule?

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  18. One of the codons on mRNA is AUG. Draw the structure of tRNA adaptor m...

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  19. Explain the dual function of AUG codon. Give the sequence of bases it ...

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  20. How can DNA segments, separated by gel electrophoresis, be visualized ...

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