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#Question id: 15637


You have isolated two mutations in the Lac operon that cause constitutive expression of Lac genes. You designate these mutants Lac1– and Lac2–. Making use of an F' that carries the Lac operon with the LacY gene mutated, you construct strains that you test for both ß-galactosidase activity and Lac permease activity with results shown below.
     
Classify each mutation as dominant or recessive and as cis- or trans-acting, giving the experimental result that allows you to arrive at each conclusion. Finally, deduce what type of Lac mutation best fits the properties of Lac 1– and of Lac 2–.

#SCPH01 Biochemistry
  1. Lac1- best fits the properties of LacOc mutations (cis-acting dominant) and Lac2- best fits the genetic characteristics of LacI-d mutations (trans-acting dominant).
  2. Lac1- best fits the properties of LacI-d mutations (cis-acting dominant) and Lac2- best fits the genetic characteristics of LacOc mutations (trans-acting dominant).
  3. Lac1- best fits the properties of LacOc mutations (trans-acting dominant) and Lac2- best fits the genetic characteristics of LacI-d mutations (cis-acting dominant).
  4. Lac1- best fits the properties of LacI-d mutations (cis-acting dominant) and Lac2- best fits the genetic characteristics of LacOc mutations (trans-acting dominant).
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TLS Online TPP Program

#Question id: 4809

#SCPH12 I Genetics

The upper most following figure above shows the locations of four genes on the genetic map of an organism; the lower figure shows the locations of the same four genes on a physical map derived from the nucleotide sequence of the DNA of that organism. The maps are not identical because

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#Question id: 4809

#SCPH28 | Zoology

The upper most following figure above shows the locations of four genes on the genetic map of an organism; the lower figure shows the locations of the same four genes on a physical map derived from the nucleotide sequence of the DNA of that organism. The maps are not identical because

TLS Online TPP Program

#Question id: 4810

#SCPH06 I Botany

In a haploid organism, the C and D loci are 8 m.u. apart. From a cross C d X c D, which of the following proportion following progeny classes: (a) C D; (b) c d; (c) C d

TLS Online TPP Program

#Question id: 4810

#SCPH12 I Genetics

In a haploid organism, the C and D loci are 8 m.u. apart. From a cross C d X c D, which of the following proportion following progeny classes: (a) C D; (b) c d; (c) C d

TLS Online TPP Program

#Question id: 4810

#SCPH28 | Zoology

In a haploid organism, the C and D loci are 8 m.u. apart. From a cross C d X c D, which of the following proportion following progeny classes: (a) C D; (b) c d; (c) C d

TLS Online TPP Program

#Question id: 4811

#SCPH06 I Botany

Three incompletely link gene as a B-A-C order. A cross allowed between AAbbcc X aaBBCC produce f1 progeny allowed test cross. Which of the following offspring is a result of double cross over?