Chapter 2.4, Problem 1LO

For the a subunit of a trimeric G protein, A. a G-protein-coupled receptor GPCR) acts as a guanine nucleotide exchange factor (GEF), whereas a regulator of G protein signaling (RGS) can act as a GTPase-activating protein (GAP). B. a GPCR acts as a GAP, whereas an RGS can act as a GEF. C. both a GPCR and an RGS can act as a GEF. O D. both a GPCR and an RGS can act as a GAP OE. None of the above.

A cell expresses a transmembrane protein that is cleaved at the plasma membrane to release an extracellular fragment. The fragment binds to receptor proteins on nearby cells and activates signaling pathways resulting in altered gene expression patterns in the cells. What form of intercellular signaling does this represent? OA. Contact-dependent signaling B. Paracrine signaling OC. Synaptic signaling D. Endocrine signaling E. Autocrine signaling

Which of the following drive nuclearly encoded proteins import into the mitochondrial matrix? OA. ATP hydrolysis OB. Membrane Potential OC. K+ Ions OD. A and B OE. None of the above

Which of the following statements is true regarding Cholesterol import into the cell? OA. It is transported within LDL B. Receptor mediated endocytosis is involved OC. Release of cholesterol occurs in the Lysosome D. All of the above are true statements OE. None of the above are true statements

In which of the following schematic drawings of signaling pathways does the activation of the receptor lead to gene expression? Activating and inhibitory steps are indicated with (+) and (-), respectively. OA OB ㅇㅂㅇㅂㅇㅁ (+) Gene Expression Activated Signaling proteins Transcription receptor activator Bl D Gene Expression Gene Expression ㅁㅁㅇ Gene Expression Gene Expression

Which of the following events normally activates a GTP-binding protein? OA. GTP hydrolysis by the protein OB. Activation of an upstream GTPase-activating protein OC. Activation of an upstream guanine nucleotide exchange factor OD. Phosphorylation of a bound GDP molecule by an upstream phosphorylase OE. Pi release after GTP hydrolysis

Proteins that are synthesized on the Rough ER are imported into the ER lumen after their signal sequence is recognized. Which of the following is responsible for the signal recognition? OA. Signal Recognition Particle, OB. Signal Sequence C. Stop-transfer sequence OD. Both B and C OE. None of the above

Stroma Light 4 H 4 H I Thylakoid- membran 2 H₂O D1 D2 Min Light 2,6 ATP 2 NADP+ 2 NADPH/H+ Fp 2,6 ADP +2,6 P 8 H+ 12 H+ 4 H+ Lumen PS II Cyt bef PS I ATP-Synthase 12345 5a 5b 6

Which of the following statements is TRUE regarding the signal recognition particle (SRP)? OA. SRP is made up of RNA and Proteins B. SRP binds to the signal sequence OC. SRP binds to the elongation factor binding site on the ribosome and pauses translation D. All of the above are true statements OE. None of the above are true statements