A new E. coli mutant was tested for auxotrophy. The mutant grows on:

minimal medium (M) + arginine (A) + proline (P)

M + P + histidine (H)

M + A + H + P

but not on M or on M + A + H. The mutant requires

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#Question id: 15337

#XL - S Microbiology

HSCs express which type of cell-surface molecule, which is the receptor for stem cell factor (SCF). It is a cytokine that exists in both membrane-bound and soluble forms and the SCF-surface molecules interaction is critical for the development, in adult animals, of multipotential progenitor cells (MPPs).  Which type of surface molecules HSCs express?

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#Question id: 15338

#XL - S Microbiology

Which cell generated on the receipt of SCF/c-Kit signaling lose the capacity for extensive self-renewal, but retain the potential to differentiate into several different hematopoietic lineages and also transiently express the molecule CD34?

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#Question id: 15339

#XL - S Microbiology

HSCs begin their life in close contact with osteoblasts located close to the lining of the endosteal cavity. Once differentiated to the pre-pro-B-cell stage, the developing B cells require Which type of signals from the chemokine, which is secreted by a specialized set of stromal cells?

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#Question id: 15340

#XL - S Microbiology

Serrogate light chain formation takes place in 

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#Question id: 15342

#XL - S Microbiology

The heavy chain is then expressed on the cell surface in combination with the surrogate light chain, which is made up of_______________, together they form the pre-B-cell receptor,

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#Question id: 15406

#XL - S Microbiology

Which method of gene transfer involves direct contact between the bacteria?