For pro-proliferation signaling pathways to cause uncontrolled proliferation, as is seen in cancer, this p53 up-regulation must not occur, It is therefore not surprising that p53 is inactive in most human tumors through loss of p53 function itself, down-regulation of positive regulators (PR) of p53 or up-regulation of negative regulators (NR) of p53, these regulators are accordingly

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#Question id: 15652

#Unit 13. Methods in Biology

You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium. You have isolated a mutation that causes constitutive melibiase activity, which you designate MelA–. P1 phage mapping experiments using a Tn5 insertion linked to Mel1 show that MelA– is not linked to Mel1. Moreover you find that when an amber suppressor is introduced into a MelA– mutant, normal melibiase regulation is restored. Classify the MelA– mutation in terms of its basic genetic properties, 

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#Question id: 5119

#Unit 5. Developmental Biology

when the presumptive eye region from a gastrula is grafted into the trunk region of another neurula, it develops to somitic tissue; whereas transplant from eye region of later stage neurula develops as an eye-like structure in host embryo. Which statement describes the results best?

 

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#Question id: 2245

#Unit 2. Cellular Organization

Which of these statements is generally true of integral membrane proteins?

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#Question id: 21392

#Unit 12. Applied Biology

In which one of the following bulk synthesis are easy?

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#Question id: 935

#Unit 1. Molecules and their Interaction Relevant to Biology

Microorganisms capable of fixing nitrogen into a form usable by animals obtain the energy for this process from ________.