chapter 11 Flashcards
quorum sensing
bacteria sensing how many of itself is around it
biofilm
an aggregation of bacterial cells that adhere to a surface
-ex. of quorum sensing
two types of mating types of yeast
a and alpha
signal transduction pathway
factors on the outside of a cell signaling a change in behavior of a cell
-ex two yeast cells mating
local signaling
cells communicating by diract contact
(only animal cells)
how do cells connect to cytoplasm of adjacent cells
cell junctions
paracrine signaling
local signaling where cells stimulate close by cells with messenger molecules
growth factors
stimulate target cells to grow oand divide
synaptic signaling
neurotransmitters are released in responce to an electrical signal
ex. drugs can effect
what does long disnance signalig
hormones
hormones
molecules used for long distance signaling
how do hormones travel to targeted cells
circulatory system
what does a cell need to respond to a hormone?
a receptor specific to that signal
what happens when a cell recieves a signal
-signal reception
-signal transduction
-cellular response
recetion
target cell detects signaling molecule that has bound to a receptor protein
transduction
when the signaling molecule alters the receptor and initiates signal transduction
response
the transducted signal triggers a specific response in target ell
ligand
signal molecule that binds to a receptor
start of signal transduction process
change in receptor shape
G protein coupled receptors
the largest family of cellsurface receptors in animals
three main types of membrane receptors
-g protein-coupled receptors
-receptor tyrosine kinases
-ion channel receptors
G protein-coupled receptors
cell-surface transmembrane receptors that work with the help of a G protein
G protein
bind to energy rich GTP, similar in structure, diverse in their functions
Receptor tyrosine kinases (RTK s)
membrane receptors that add a phosphate group from atp to a tyrosine of another protein
- can trigger multipe STP at once —> cancer
ligand-gated ion channel
receptpr acts as a gate that opens and closes when the receptor chamges shape
intracellular receptros
proteins found in cytoplasm or nucleus of target cells
protein kinase
transfer phosphates from ATP to a protein
phosphorylation cascade
when there a lot of molecules that rely on protein kinase
secomd messengers
small, nonprotein, water soluble. molecules that spread throughout a cell by diffusion
- common: Cyclic AMP and calcium ions
cyclic AMP (cAMP)
a small molecule produced from ATP ( one of most common second messangers)
what does Cholerae do
makes G protein stay active and produce a ton of salt and a ton of water —> diharrea
Calcium ion (Ca^2+)
used widley as a second messanger
