Different types of peanuts. Not every peanut is the same! There are thousands of different types of peanuts, these are known as different cultivars. We can distinguish four popular different types of peanuts: the Runner peanut, the Virginia peanut, the Valencia peanut and the Spanish peanut. All these peanuts differ in size, color, flavor and oil content and are often used for very different purposes.
For a signal molecule to bind with an intracellular receptor it must be able to pass through the cellular membrane. Generally signal molecules that enter the cell are nonpolar and fat soluble. These signal molecules can pass through the lipid bilayer of the cell membrane.
Cell surface receptors are receptors that are embedded in the membranes of cells. They act in cell signaling by receiving extracellular molecules. They are specialized integral membrane proteins that allow communication between the cell and the extracellular space. The extracellular molecules may be hormones, neurotransmitters, cytokines, growth factors, cell adhesion molecules, or nutrients; they react with the receptor to induce changes in the metabolism and activity of a cell. In the process