Few mutants (column A) and their results (column B) are listed in the table given below:

Column A	Column B
A. Gain-of-function of Ski	I. Inhibits the ability of activated type I TGF-β receptors (RI) to phosphorylate R-Smad proteins
B. Loss-of-function of RII receptor	II. Transcription activation induced by TGF-β and mediated by Smad complexes is shut down
C. Gain-of-function of smad-7
D. Loss-of-function of R-smad

Match the correct mutation with the observe result?

#Question id: 2214

#Unit 2. Cellular Organization

Which of the following is true about glucose transporters?

#Question id: 2215

#Unit 2. Cellular Organization

Which statement describes the mode of action of the ABCB1 transporter (the first eukaryotic ABC transporter to be recognized)?

#Question id: 2216

#Unit 2. Cellular Organization

Gorter and Grendel's earliest evidence that membranes were formed from a lipid bilayer included:

#Question id: 2217

#Unit 2. Cellular Organization

In immunofluorescence studies you always see the small G-protein Ras in a specific region of the cell and, given its protein sequence along with many other proteins localized to this area, you hypothesize that their C-terminal Cys-Ala-Ala-X (X can be any amino acid) motifs may be responsible for targeting these proteins to this subcellular region. To test this hypothesis, you genetically engineer the sequence encoding this motif onto a cDNA encoding green fluorescent protein. When immunofluorescence is used, where specifically would you expect to see GFP localized in the cell?

#Question id: 2218

#Unit 2. Cellular Organization

Human alkaline phosphatase protein is attached to the plasma membrane by a GPI anchor. In an experiment you treat cells with each of the following enzymes and find one of them inhibits the activity of the protein because it releases it into the extracellular matrix. Which specific enzyme led you to conclude that this anchor on alkaline phosphatase was both necessary and sufficient for binding the protein to the membrane where it can perform its normal activity?

#Question id: 2219

#Unit 2. Cellular Organization

Cholesterol and phospholipids are transported between organelles by

i. Golgi-dependent mechanisms.

ii. incompletely characterized vesicle populations.

iii. direct contact between membranes and, to some extent, small, soluble lipid-transfer proteins.

Which of the following statements are correct?