BIO 1140 Lecture 11: Biology Lecture 11
Document Summary
Alp - neural activity involves transmission of information via electrical events; in contrast, endocrine activity involves transmission of information by hormone transport to target tissues. Alp - the target tissues for steroids do not have receptors for them on the membrane surface because steroids are soluble in the lipid bilayer. The communication path taken to reach target cell. Their mode of action / interaction with the cell and receptors. Lipophilic - cannot be stored in vesicles (endocrine path) Will diffuse or be bound to transport, be imbedded in membranes, bind them to soluble proteins to keep them in. Membrane permeable - can reach intracellular receptors. Receptors inside the cell (cytoplasm or nucleus) Acts upon itself - one that secrets binds as well. 2 main pathways lead to 2 main classes. Hydrophilic so can be packaged in vesicles. Derived from nitrogenous bases adenine or guanine. Need a transporter or can use exocytosis.