9 In your study of a new bacterial species you have identified a transducing phage that you call Px. In addition you have worked out methods to make random transposon insertions into the bacterial genome. You have generated two different transposon insertion collections one with 105 random Tn5 (Kanr) insertions and the other with 105 random Tn10 (Tetr) insertions. You grow Px phage on the mixed collection of Tn5 insertions and use the resulting phage lysate to infect the mixed collection of Tn10 insertions. You select 10,000 Kanr  transductants and find that 80 of them are Tets. Use this information to estimate the total size of the bacterial genome assuming that both Tn5 and Tn10 insert randomly and that the average size of a fragment recombined into the recipient genome during Px transduction is 55 kbp. (Tn5 is about 5 kbp and Tn10 is 10 kbp.)

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#Question id: 2917

#Unit 2. Cellular Organization

With respect to the interconversion between open and condensed chromatin shown below: Which of the directions (i) or (ii) would you anticipate would be the consequence of the following types of chromatin modification?

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#Question id: 5105

#Unit 5. Developmental Biology

Cells transplanted from the neural tube of a frog embryo to the ventral part of another embryo develop into nervous system tissues. This result indicates that the transplanted cells were________.

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#Question id: 10412

#Unit 6. System Physiology – Plant

Red and far-red lights are perceived by plants through various photoreceptors including phytochromes. The red/far-red reversibility of seed germination was due to the-

a) photoreversibility of phytochrome

b) presence of red and far-red light at different fluence rate

c) Conversion of Pr to Pfr form through the effect of red light

d) equal proportion of red and far red light at same fluence rate

Which of the following combinations is correct?

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#Question id: 5555

#Unit 5. Developmental Biology

The formation of the fertilization envelope requires an increase in the cytosolic concentration of ________.

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#Question id: 28208

#Unit 5. Developmental Biology

which of the following factor is a diffusible biochemical molecule that can determine the fate of a cell by its concentration?