Biosignalling Flashcards
What is cell signalling?
Signal transduction is the process by which cells can respond to changes in their environment.
What is the role of intracellular signalling molecules?
They can amplify the signal received - a few extracellular molecules are enough to evoke a large intracellular response.
What is the role of extracellular signalling molecules?
They bind to specific protein receptors and can initiate a cascade of signalling events inside the cell.
What are the four types of intracellular signalling?
Endocrine, paracrine, neuronal & contact dependent.
What is endocrine intracellular signalling?
Signalling molecules from one cell travel to other cells via the blood stream.
What is paracrine intracellular signalling?
The signalling molecules from one cell act on the cells in the immediate surrounding area.
What is neuronal intracellular signalling?
The signalling molecules are released from the end plate of a neuronal cell & travel across a synapse to the receptors on the target cell.
What is contact dependent intracellular signalling?
The signalling molecules are expressed on the cell surface of one cell and bind to the receptors of another cell when the two come into contact.
What does cell response mean?
It is the sum of all the signals it receives.
A cells response to a signal can be fast or slow.
What do fast responses involve?
They involve altering the protein function in the cell.
This leads to altered cytoplasmic behaviour and altered cell response.
What do slow responses involve?
They involve altering gene expression.
This leads to increasing/decreasing the synthesis of proteins.
Where can receptors be found?
On the cell surface membrane or intracellularly.
