C2.2 Flashcards
State the function of the following neuron cell parts: dendrites, axon and cell body.
Identify the cell body, axon and dendrites in diagrams of typical sensory and motor neurons.
Define membrane potential.
Define resting potential.
Outline three mechanisms that together create the resting potential in a neuron.
State the voltage of the resting potential.
Outline the six steps of sodium-potassium pump action.
Define action potential.
Explain the difference in nerve impulse speed for myelinated and unmyelinated fibers.
Define nerve impulse.
State the correlation between conduction speed of nerve impulses and animal size.
Outline the correlation between conduction speed of nerve impulses and axon diameter.
Define synapse, synaptic cleft and effector.
List examples of effector cells.
State that a signal can only pass in one direction across a typical synapse.
State the role of neurotransmitters.
Outline the mechanism of synaptic transmission occurring at a presynaptic cell, including the role of depolarization, calcium ions, exocytosis and diffusion.
State that neurotransmitters can either be excitatory or inhibitory.
Outline the mechanism of synaptic transmission occurring at a post-synaptic cell, including the role of neurotransmitters, diffusion, receptors, gated ion channels, threshold potential and action potential.
State that calcium functions as a chemical signal triggering exocytosis of neurotransmitter from a presynaptic cell.
State that acetylcholine is one of the most common neurotransmitters in both invertebrates and vertebrates and is used as the neurotransmitter in many synapses including between neurons and muscle fibers.
Outline the digestion of acetylcholine by acetylcholinesterase.
State that an action potential is only initiated if the threshold potential is reached.
Define depolarization.
Outline the mechanism of depolarization during an action potential using voltage gated sodium channels.
Define repolarization.
Outline the mechanism of repolarization during an action potential using voltage gated potassium channels.
Describe the movement of sodium ions in a local current.
State that local currents cause each successive part of the axon to reach the threshold potential.
Explain how the movement of sodium ions propagates an action potential along an axon.
Outline the cause and consequence of the refractory period after depolarization.
Outline the use of oscilloscopes in measuring membrane potential.
Annotate an oscilloscope trace to show the resting potential, action potential (depolarization and repolarization), threshold potential and refractory period.
Deduce the number of nerve impulses per second from an oscilloscope trace.
Describe the structure of a myelinated nerve fiber.
Outline how the myelination of neurons allows for saltatory conduction, in which the differences in the distribution of electrically charged ions across the membrane can effectively jump from node of Ranvier to node of Ranvier.
State that in myelinated neurons, the gated and non-gated Na+ and K+ ion channels are clustered down the axon at nodes of Ranvier.
Define exogenous chemicals.
Outline the effects of neonicotinoids on synaptic transmission.
Outline the effects of cocaine on synaptic transmission.
Compare inhibitory and excitatory neurotransmitters.
Outline the inhibitory mechanism of the neurotransmitter GABA.
Outline the consequence of hyperpolarization by inhibitory neurotransmitters.
Describe the effects of excitatory and inhibitory neurotransmitters on the ability of a postsynaptic cell to reach its threshold potential.
Define summation.
Interpret graphical representations of the summation of combinations of excitatory and inhibitory neurotransmitters.
Describe the mechanism by which environmental stimuli are able to activate nerve endings in the skin, including the role of receptor proteins, ions channels, and threshold potential.
Define emergent property.
List stimuli which can trigger a pain response.
Outline the flow of information during the pain response.
State that new properties emerge at each level of biological organization.
Outline consciousness as an emergent property.
