<span>In the sentence "Biologists recognize the following levels of cell organization: _____, the choice that correctly completes the sentence is b. cellular, tissue, organ, system, and organism. A cell is the basic unit of living organisms. The group of similar cells that work together to perform a specific job is a tissue. The group of multiple tissues joined together in the functional structure is an organ. Functionally related organs form organ systems, which all together form one organism.</span>
Sure what is it , where is it
<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.
