M1 Communication Flashcards
What is cell signalling?
Communication between cells
Give two examples of cell signalling
1) neuronal system - network of neurones that signal to each other across synapse junctions
2) hormonal system - uses blood to transport it’s signals
Define “negative feedback”
Response to a change in conditions that acts to reverse that change
Define “positive feedback”
When a small change brings about an increase in that change
Define “homeostasis”
Maintenance of a constant internal environment
Explain the principles of homeostasis
Homeostasis monitors factors (such as pH) using receptors. A negative feedback mechanism then controls the action of effectors that reverse any internal change.
Why do multicellular organisms need communication systems?
They need to be able to respond to changes in their internal and external environment and they need to coordinate the activities of different organs
