Yes they do just like we do
        
             
        
        
        
<h3><u>Answer;</u></h3>
b). Activation of an upstream guanine nucleotide exchange factor
<h3><u>Explanation</u>;</h3>
- <em><u>When a ligand activates the G protein-coupled receptor, it induces a conformational change in the receptor that allows the receptor to function as a guanine nucleotide exchange factor (GEF) that exchanges GDP for GTPthus turning the G protein-coupled receptor on.</u></em>
- The activated G-protein then dissociates into an alpha (G-alpha) and a beta-gamma complex. 
 
        
        
        
that's all wrong the real answer is b.99.3