Cell communication Flashcards
gap junctions
directly connect two cells allowing various molecules, ions and electrical currents to pass from cell to cell in both directions
What type of junction allows cells to communicate via electrical transmission
gap junctions
autocrine communication
cell produces chemical/ hormone that affects itself
paracrine communication
one cell to many cells
cell produces a signal to induce changes in nearby cells
used in the immune system
endocrine system
many cells to many cells
chemicals (hormones) released to the bloodstream and sent all over the body.
can only act on cells with specific receptors (target cells)
how does chemical transmission occur between one cell to one cell
chemical synapse
one way
pros cons and examples of nerve transmission
rapid response quick transmission very specific actions localised e.g voluntary muscle movement
pros cons and examples of hormone communication
co-ordinated body wide reactions
slow to act but effects last
e.g menstrual cycle, insulin
first messenger
chemical transmitter that acts on receptor
what is a type of transmitter that can pass through the membrane
steroid transmitters
examples of 2nd messengers
calcium ions
cAMP
describe the process of G proteins and cAMP
1 - transmitter binds to a membrane receptor
2 - G protein is activated by GTP
3 - ATP is converted to cAMP by adenyl cyclase
4 - cAMP activates an enzyme called protein kinase
5 - this activated a specific enzyme that catalyses a chemical reaction in the cell
describe calcium as a 2nd messenger
1 - transmitter binds to a membrane receptor
2 - activates a g -protein which activates the enzyme phospholipase C
3 - this causes opening of Ca channels allowing Ca to enter
4 - Ca binds to a protein forming a complex which acts as a 2nd messenger
