Week 5 Flashcards
ligands
messengers/signal
receptor
what ligands bind to
specificity
is the receptor activated or not?
affinity
how well does the ligand bind to the receptor?
saturation
% of receptors that are bound to ligands
agonist
binds to receptor and causes a shape change/response
antagonist
binds to receptor but does not cause a response
location of nonpolar receptors
cytosol or nucleus
location of polar receptors
integral protein/membrane bound
what type of nonpolar ligand has issues traveling through the polar interstitial fluid?
endocrines
how do nonpolar endocrines travel through polar IF?
plasma binding proteins
why do the nonpolar endocrines bind to plasma binding proteins?
they are amphipathic, polar areas interact with IF and nonpolar interacts with endocrine
what type of response do nonpolar ligands cause?
change in transcription (increase or decrease)
do polar ligands have trouble passing through the interstitial fluid?
no, polar and polar
can polar ligands enter the cell?
no
where are the receptors that polar ligands bind to?
the cell membrane
how does the message from polar ligands reach the inside of the cell?
multiple messengers, “relay”
what is the most common response from a polar neurotransmitter?
change in charge distribution
what are the two possible responses from polar ligands?
change in charge distribution and activation of enzymes
what happens when an enzyme is activated?
amplification, the message is passed at a greater rate
how does a cell decrease activation?
catabolize ligand before it reaches the cell or catabolize receptor
how is a receptor catabolized?
decrease affinity (change shape or charge) or endocytose receptors
how is insulin resistance developed?
cell is constantly being told to put GLUTS on the surface by insulin, cells endocytose receptors
how does a cell increase activation?
anabolize (intracellular) and exocytose receptors (membrane-bound)
what makes up the CNS?
brain and spinal cord
what makes up the PNS?
efferent and afferent neurons
what are the two main functions of the nervous system?
communication and processing
what is the function of a cell body of a neuron?
form neurotransmitter to be sent out and protein production
dendrites
receive information, processes from the cell body
axon (nerve fiber)
transportation system for neurotransmitters
axon terminal
branched end of the axon that releases neurotransmitters
myelin
separate cells that wrap their plasma membrane around the axon, insulates and protects
what type of myelin cells are found in the PNS?
schwann cells
how many schwanns cells per section of myelin?
1
what type of myelin cells are found in the CNS?
oligodendrocytes
how many neurons per one oligodendrocyte?
multiple, space is limited
what are the breaks in myelin on an axon called?
nodes of ranvier
what is the function of nodes of ranvier?
give access to the ECF
afferent neuron
receptor to CNS
what is special about afferent neurons?
no dendrites, 2 axon terminals
how do afferent neurons receive and send signals?
using the axon
efferent neurons
signals from CNS
interneuron
from afferent to efferent neurons, in CNS, defines/makes up CNS
what type of neuron is the most abundant?
interneurons
what type of neuron is the mid-sized compartment?
efferent
what type of neuron is the least abundant?
afferent
what are the two synapse types?
electrical and chemical
what type of synapse is faster?
electrical
what type of synapse is the most abundant?
chemical
why are chemical synapses the most abundant?
they are unidirectional
what is an example of an electrical synapse?
gap junction
what is an example of a chemical synapse?
NT release sites
what is a presynaptic neuron?
neuron sending the message
what is a postsynaptic neuron?
neuron receiving the message
convergence
more presynaptic neurons communicating to less postsynaptic neurons
divergence
less presynaptic neurons communicating to more postsynaptic neurons
membrane potential
difference in charge across the membrane due to the distribution of charged components
what kind of cells have membrane potential?
all of them
electrochemical gradient
net gradient (chemical and electrical)
