A signal reaches a cell mostly in the form of a signalling molecule binding to a receptor on the cell surface. This binding activates a chain of events that amplifies the signal and transfers it inside the cell. Protein kinases phosphorylate proteins and cause their activation or deactivation, or in general modify their activity. When a signalling molecule binds to a receptor, a cascade is activated and the second messengers, such as cAMP, are synthesized. cAMP molecules activate the protein kinases, which phosphorylate specific proteins and activate them.
The fossil record provides evidence of Earth’s changes over time. It's a record keeper of the Earth'd changes over time.
Answer:
ur going to injure your anterior tibialis muscle XDD
~batmans wife dun dun dun...aka ~serenitybella
The answer is urticaria (also known as hives).
