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TLS Online TPP Program

#Question id: 1262

Although MAP kinase is often activated in multicellular animals by RTKs or cytokine receptors, signaling from other receptors can activate MAP kinase in other eukaryotic cells. we consider the mating pathway in the yeast S. cerevisiae, a well-studied example of a MAP kinase cascade linked to G protein–coupled receptors (GPCRs). Which of the following statement is incorrect?

#Unit 4. Cell Communication and Cell Signaling

  1. An a haploid cell secretes the a mating factor and has GPCRs for the α factor on its cell surface; an α cell secretes the α factor and has GPCRs for the a factor. Thus each type of cell recognizes the mating factor produced by the opposite type.

  2. Ligand binding and dissociation of the G protein subunits, the membrane-tethered Gβγ subunit binds the Ste5 scaffold to the plasma membrane.

  3. Gβγ also activates Cdc24, a GAP for the Ras-like protein Cdc42; the active, GTP-bound Cdc42, in turn, binds to and activates the Ste20 kinase.

  4. Ste20 then phosphorylates and activates Ste11, which is analogous to Raf and other mammalian MEK kinase (MEKK) proteins. Ste20 thus serves as a MAPKKK kinase.

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TLS Online TPP Program

#Question id: 3047

#Unit 2. Cellular Organization

A rapidly growing bacterial species such as E. coli exhibits a typical phase of growth cycle in liquid nutrient broth. If a bacterial culture has starting density 1000 cells/ml in log phase and after four hours cell density is 4000 cells/ml.  What is specific growth rate per hour? 
TLS Online TPP Program

#Question id: 9599

#Unit 6. System Physiology – Plant

The primary donor of PSI, P700, is a dimer of chlorophyll a molecules, in primary donor chlorophyll, additional chlorophylls molecules such as
TLS Online TPP Program

#Question id: 4791

#Unit 8. Inheritance Biology

Body color in mice, YY is a recessive lethal, Yy yellow, yy gray and hair type straight is dominant over fuzzy. A geneticist crosses two yellow mice with heterozygous straight hair. Which the observe ratio is of obtains following progeny?
TLS Online TPP Program

#Question id: 1085

#Unit 4. Cell Communication and Cell Signaling

Which of the following statements about a G protein signaling pathway is true?
TLS Online TPP Program

#Question id: 19302

#Unit 12. Applied Biology

The assembly of various DNA sequences designed for easy identification of the construct and its efficient expression is termed as