Home
Class 12
BIOLOGY
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 phenomena.

Text Solution

Verified by Experts

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
Promotional Banner

Topper's Solved these Questions

  • GENETICS AND EVOLUTION

    TRUEMAN BIOLOGY|Exercise SECTION-C|45 Videos

  • GENETICS AND EVOLUTION

    TRUEMAN BIOLOGY|Exercise SECTION-D|25 Videos

  • Genetics

    TRUEMAN BIOLOGY|Exercise ASSERTION AND REASON|123 Videos

  • HUMAN HEALTH AND DISEASE

    TRUEMAN BIOLOGY|Exercise MULTIPLE CHOICE QUESTIONS|210 Videos

Similar Questions

Explore conceptually related problems

Go though the following statements (i) Meselson & stahl used cesium chloride density gradient to distinguish heavy DNA molecules from the normal DNA molecules. (ii) In meselson & Stahl experiment the DNA that was extracted from the culture one generation after the transfer from .^(15)N to .^(14)N , was composed of equal amount of hybrid (intermediate) DNA and of light DNA. (iii) In prokaryotes, control f the rate of transcriptional initiation is the predominant site for control of gene expression. (iv) In lac operon, the repressor is synthesised only at the time when the level of metabolite is in excess. Find out the correct statements?

How does the total surface area of a box change if (i) Each dimension is doubled? (ii) Each dimension is tripled? Express in words .Can you find the total surface area of the box if each dimension is raised to n times?

A bucket of turbid river water does not become clear even on standing for a long time. Why? How can you make this turbid water clear? Explain.

Express your opinion as an environmentlist which things you could include in PBR. 'Asthma occurs due to human activity'-Judge the logic of the statement.

Express your opinion as an environmentalist which things you could include in PBR. 'Asthma occurs due to human activity'-Judge the logic of the statement.

Equivalent weights of two metals A and B are same , but atomic mass of A is 1.5 times of that of B . How can you explain this ?

The half-life of I^131 is 8d. If a sample of I^131 is taken at time t=0, then it can be said that (A) No nuclear disintegration will occur before t=4 d. (B) No nuclear disintegration will occur before t=8 d. (C) all nuclei will be disintegrated in t=16 d. (D) A definite nucleus may be disintegrated at any time after t=0.

How many words, with or without meaning, can be formed using all the letters of the word EQUATION at a time so that the vowels and consonants occur together?

TRUEMAN BIOLOGY-GENETICS AND EVOLUTION -SECTION-A
  1. A low level of expression of lac operon occurs at all the time. Can yo...

    Text Solution

    |

  2. Which Mendel's law of inheritance is universally acceptable and withou...

    Text Solution

    |

  3. Name the parts 'A' and 'B' of the transcription unit given below.

    Text Solution

    |

  4. Name the components 'a' and 'b' in the nucleotide with a purine, given...

    Text Solution

    |

  5. Why hnRNA is required to undergo splicing?

    Text Solution

    |

  6. State any one reason to explain why RNA viruses mutate and evolve fast...

    Text Solution

    |

  7. How is the length of DNA usually calculated?

    Text Solution

    |

  8. How does HIV differ from bacteriophage?

    Text Solution

    |

  9. The gene I that controls the ABO blood grouping in human beings has t...

    Text Solution

    |

  10. Provide one word or one sentence information about 'plasmid' with resp...

    Text Solution

    |

  11. Name the event during cell division that results in the gain or loss o...

    Text Solution

    |

  12. Mention the contribution of genetic maps in human genome project.

    Text Solution

    |

  13. Name one autosomal dominant and one autosomal recessive. Mendelian dis...

    Text Solution

    |

  14. A human being suffering from Down's Syndrome shows trisomy of 21^(st) ...

    Text Solution

    |

  15. A pedigree chart given here, presents a particular generation which sh...

    Text Solution

    |

  16. In order to obtain the F(1)-generation Mendel pollinated a pure-breedi...

    Text Solution

    |

  17. "Genes contain the information that is required to express a particula...

    Text Solution

    |

  18. How are alleles of particular gene differ from each other? Explain its...

    Text Solution

    |

  19. For the experssion of traits genes provide only the potentiality and t...

    Text Solution

    |

  20. A, B, D are three independently assorting genes with their recessive a...

    Text Solution

    |

  21. Sometimes cattle or even humen beings give birth to their young ones t...

    Text Solution

    |