Chapter 6 - Communication & Homeostasis Flashcards
direct contact communication where chemical and/or electrical signals and diffuse through cytoplasm
gap junctions
two direct contact forms of communication between cells
gap junctions, contact-dependent signals
direct cell contact communication require interaction between membrane molecules and transfers signals in both directions
contact-dependent
cell communication that is a local signal and the ligand is released into the ECF… two methods
autocrine signals, paracrine signals
local cell communcation signal that acts on the same cell that secreted them
autocrine signals
local cell communication signal that diffuse to act on adjacent cells
paracrine signals
neurotransmitters are secreted by blank that diffuse across a blank to the blank cell
neurons, synapse, target
diffusion distance of neurotransmitters is blank but the neuron is blank
short, long
hormones are secreted by blank glands or cells directly into the blank system
endocrine, circulatory
target cells only respond if they have blank for blank
receptors, ligand
neurohormones are released by blank directly into the blank…. called blank
neurons, blood, neuroendocrine
neurohormones are blank so they travel blank in blood
polar, fast
these may act as both local and systemic signals
cytokines
all nucleated cells secrete blank following stimuli
cytokines
cytokines in development & differentiation is blank
autocrine/paracrine
cytokines in stress and inflammation is blank
paracrine/endocrine
if ligand has blank then it cannot cross blank on its own so receptors must be on the blank
charge, membrane, outside
if ligand is non polar then it can go through the cell blank so the receptor location can be anywhere on the blank of the cell
membrane, inside
four types of membrane receptors
receptor channel (chemically gated ion channels), receptor-enzyme, G protein coupled receptor, integrin receptor
all membrane receptors begin with a binding to blank
ligand
integrin receptor binds to ligand then changes what
shape of the entire cell
receptor enzyme binds to ligand which triggers release of blank
enzyme
G protein coupled receptor binds to ligand which sends another signal to blank
something else to perform an action
receptor channel membrane receptors are the blank
fastest
G protein receptors are the blank
slowest
all membrane receptors require blank to change ICF environment
signal transduction
this occurs in signal transduction where small amounts of ligand have blank cellular effects
big, amplification
signal transduction has a blank response to a single ligand, this is called blank
coordinated, diversification
overlapping transduction pathways for multiple controls for each response
redundancy
G proteins bind to these two nucleotides
GDP, GTP
GDP is blank
inactivated
GTP is blank
activated
amplifier enzymes convert one thing into something that creates…
another active substance that actually performs a function
for example… viagra does not cause someone to have erection but once you get one then it takes longer to blank
go away
lipid derived paracrine signals produced by the arachidonic acid cascade
eicosanoids
eicosanoids are produced by the blank acid cascade
arachidonic
these are leukocytes that cause bronchoconstriction
leukotrienes
inflammation in tissues caused by
prostaglandins
the natural ligand activates a receptor and a direct blank also activates the same receptor
agonist
a direct blank blocks receptor activity
antagonist
direct agonists and antagonists bind blank to the receptor
directly
in signal pathways, there are these two things because receptors can bind to multiple ligands
specificity/competition
alpha adrenergic receptors cause blank
vasoconstriction
beta adrenergic receptors cause blank
vasodilation
both types of adrenergic receptors only bind epinephrine and norepinephrine
specificity
epinephrine and norepinephrine compete for same active site
competition
alpha receptors have a higher affinity for blank
norepinephrine
beta receptors have a higher affinity for blank
epinephrine
blank is a more potent vasoconstriction
norepinephrine
protein activity at maximum rate and is true for enzymes and receptors
saturation
increase in number of receptors
up-regulation
up regulation using isoforms can change blank but binding will still be more than normal
speed
decrease in number of receptors and decrease in binding affinity
down regulation
regulated variable = blank
parameter
what detects temp in our bodies
hypothalamus
this is always on but like a dimmer switch
tonic control
paracrine and autocrine signals are blank control pathway
local
synaptic, endocrine, and neuroendocrine control pathway
reflex
why is it good to have complex control pathways?
more steps are like more shock absorbers so the hormone at the end will not vary too much
The binding of lipophilic messengers, such as steroid hormones, to their receptors triggers
gene transcription
forcing an animal to adapt to a certain change in their environment
acclimation
two hormones controlling circadian rhythms
melatonin, cortisol
slows down metabolic rate
melatonin
hormone that prepares body for the day
cortisol
anticipatory response is called
feedforward
