unit 1 flashcards
STUDY
ECF is inside or outside the cell
outside think of E as in EXIT
IUF is inside or outside the cell
inside: think of I as INside
what are the three feedback mechanisms and provide a brief description
- negative feedback: when something increases the other responding factor will decrease
- feedforward: change has not yet happened but body has anticipated it to happen
- positive feedback: because one thing increased it caused something else to increase –> NOT HOMEOSTATIC.
What is an example if feedforward feedback mechanism
ex) you are a runner at the start line, waiting for the gun to go off to signal the start of the race. you are ready and anticipate that the gun is going to go off at any second. it has not went off yet but your heart is already racing, nerves are kicking in and BP is increasing. these changes were made even tho nothing has happened yet you have just anticipated it.
explain the difference between local and reflex response
local: located in one local spot for example your muscle but NOT your whole body
- results in local change/ response
- short
reflex: neural or endocrine
- longer
- throughout the whole body
- usually follows with stimulus –> integrating centre–> response
what signal is most responsible for cell communication
chemical signals
_________ cells: cells that respond to stimulus
target cells
majority of signals that make things work in our body are the ________ _________ ________ __________ that use surface receptors
majority of signals that make things work in our body are the WATER SOLUBLE NON-LIPOPHILLIC that use surface receptors
What are the two types of long range cell - cell communication
- endocrine
- neural
what cell - cell communication is explained in this definition:
- hormone release in blood stream
- receptor needed
endocrine
what cell - cell communication is explained in this definition:
- signals sent along axon
- transmits info to next cell
neural
length of NEURAL cell- cell communication depends on what
- how long the neurons axon is
- how many neurons are in the chain
definition of neuroendocrine
NEURAL + ENDOCRINE
electrical signals travel down neuron (neuro) ; reaches end and is secreted into the blood (endocrine)
receptors are proteins that:
1.
2.
- project to outside the membrane
- within the cell
receptor proteins can be on plasma membrane or within the cell.
true or false?
water soluble = hydrophobic = lipophobic –> surface protein
false,
not hydrophobic it is water soluble so hydrophilic.
water insoluble = hydrophobic = lipophillic –> intracellular protein
true
what are 2 examples of down stream mechanisms
(dont think this is very important)
- protein kinases
- Ca2
- phosphorylated proteins
- activated Ca 2+ binding proteins
what is CHOLERA?
- its an intestinal infection
- comes from contaminated food ( developed countries) and water ( developing countries)
- need alot of this bacteria to cause this infection approx 100 million bacteria for healthy individuals, less is needed for compromised individuals ( young children, immune suppressed, people with reduced gastric acidity
what is tonic control?
when one thing increases the other thing does as well.
ex) increase norepinephrine = increase time
–> it supports the other factor
what is antagonist control
when one thing decreases the other increases
ex) increase in sympathetic HR neuron = decrease in parasympathetic HR neuron
–> opposites
in terms of GPCR (G- PROTEIN COUPLED RECEPTOR) is GTP the active state or does GDP signify the active state and why?
GTP because the alpha and beta y subunits are separated. with GDP they are attached together
true or false G alpha subunit turns itself off by hydrolyzing (loosing a phosphate) GTP
true GTP is active state because alpha and beta y subunits are separated. when hydrolysis occurs the phosphate is lost making it no longer GTP but GDP (di-phosphate) (2) –> which = the inactive state as alpha and beta y subunits are attached
difference between central and peripheral receptors?
Think of it as CNS and PNS
PNS: part of your nervous system that lies outside your brain and spinal cord
CNS: is made up of the brain and spinal cord:
difference between the two is that central receptors are in or close to the brain and peripheral receptors lie outside the brain
3 examples of Central receptors
- eyes (vision)
- ears (hearing)
3 nose (smell)
4 tongue (taste)
3 examples of peripheral receptors
- chemoreceptor (pH, gasses, chemcial)
- osmoreceptor (osmolarity)
- thermoreceptor (temp)
- baroreceptor (pressure)
- proprioceptor (body position)
- mechanoreceptor (pain, vibration, touch)
