Signaling Pathways Producing Multiple Effects on Cells Or Organisms-
In order to respond to changes in their immediate environment, cells must be able to receive and process signals that originate outside their borders. Individual cells often receive many signals simultaneously, and they then integrate the information they receive into a unified action plan. But cells aren't just targets. They also send out messages to other cells both near and far.
At any one time, a cell is receiving and responding to numerous signals, and multiple signal transduction pathways are operating in its cytoplasm. Many points of intersection exist among these pathways. For instance, a single second
messenger or protein kinase might play a role in more than one pathway. Through this network of signaling pathways the cell is constantly integrating all the information it receives from its external environment.
Cells typically receive signals in chemical form via various signaling molecules. When a signaling molecule joins with an appropriate receptor on a cell surface, this binding triggers a chain of events that not only carries the signal to the cell interior, but amplifies it as well. Cells can also send signaling molecules to other cells. Some of these chemical signals — including
neurotransmitters — travel only a short distance, but others must go much
farther to reach their targets.
At any one time, a cell is receiving and responding to numerous signals, and multiple signal transduction pathways are operating in its cytoplasm. Many points of intersection exist among these pathways. For instance, a single second
messenger or protein kinase might play a role in more than one pathway. Through this network of signaling pathways the cell is constantly integrating all the information it receives from its external environment.
Cells typically receive signals in chemical form via various signaling molecules. When a signaling molecule joins with an appropriate receptor on a cell surface, this binding triggers a chain of events that not only carries the signal to the cell interior, but amplifies it as well. Cells can also send signaling molecules to other cells. Some of these chemical signals — including
neurotransmitters — travel only a short distance, but others must go much
farther to reach their targets.