cell communication Flashcards
1
Q
purpose of cell communication
A
- communication for development
- communication for homeostasis
- however communication breaks down in old age
2
Q
characteristics of signals
A
- duration
- speed
- mechanism
- range
- specificity
- form of signal
3
Q
contact-dependent communication
A
cell-to-cell direct communication
very short range
4
Q
synaptic communication
A
communication via neurotransmitters along an axon
short-medium transport
5
Q
paracrine communication
A
local transmission to surrounding cells via a local mediator
6
Q
endocrine communication
A
hormones through bloodstream
7
Q
types of response to signals
A
- be in form of gradient = morphogen gradient
- cells can react in different ways on the basis of the strength of the signal
8
Q
possible downstream effects of receptor stimulation
A
metabolism for enzyme
gene expression
changes in cell shape/movement
9
Q
factors affecting speed of response
A
- changing the structure of an existing protein eg. ion channel (very fast)
- changing the post translational modification eg phosphorylation (quite fast)
- changing protein levels via gene expression (slow)
10
Q
how does signal regulation occur?
A
regulation of enzymes such as kinases and phosphatases which take part in mechanisms
- positive and negative feedback
