CSB332 Exam
Lecture 1
Cells of the Nervous System
Neuron – in the form of sensory, motor and interneurons -> transmit info using electrical signaling
Glial Cells – metabolic support, protection and insulation for neurons
Cell body – contains nucleus, other organelles – ex. mitochondria for ATP
Dentrites – branches which incoming fibers make connections
- receiving stations for excitation or inhibition
- covered with short dendritic spines that increase SA
- dendrites and their spines are constantly modified and can change rapidly in response to changes in synaptic transmission: #, size, shape, etc
Axon – conducts electrical signals from cell body to terminal
Transmission occurs from presynaptic to postsynaptic cell
Flow of information: synapse -> dendrite -> soma -> axon -> synapse
Lecture 2 – Chapters 4 & 5
Ion channels and signalling
- ions are separated by cell membrane; when ion channels are opened, ions flow -> generating electrical signals -> so neurons can communicate info through these electrical signals
- neurons generate a constant negative voltage across membrane: the rmp
- an AP abolishes the –ve rmp, making membrane potential transiently positive
- we can record and measure ion currents using electrophysiology
- hyperpolarization is usually the movement of +ve ions moving outward, but it can also be the movement of –ve ions moving inward; while depolarization is the opposite
How do these membrane potentials arise?
- electrical signals are generated through action of ion channels by opening and closing
- the membrane bi-layer is impermeable to ions (polar/hydrophilic faces outward; nonpolar/hydrophobic faces inward)
- ions cross membrane passively through ion channels (movement of ions driven passively by the difference of gradient across membrane); or actively through transport molecules (pumps/transporters)
- both ion channels and transport molecules are membrane-spanning proteins (transmembrane)
General features of an ion channel
- central water-filled pore
-
Cells of the Nervous System
Neuron – in the form of sensory, motor and interneurons -> transmit info using electrical signaling
Glial Cells – metabolic support, protection and insulation for neurons
Cell body – contains nucleus, other organelles – ex. mitochondria for ATP
Dentrites – branches which incoming fibers make connections
- receiving stations for excitation or inhibition
- covered with short dendritic spines that increase SA
- dendrites and their spines are constantly modified and can change rapidly in response to changes in synaptic transmission: #, size, shape, etc
Axon – conducts electrical signals from cell body to terminal
Transmission occurs from presynaptic to postsynaptic cell
Flow of information: synapse -> dendrite -> soma -> axon -> synapse
Lecture 2 – Chapters 4 & 5
Ion channels and signalling
- ions are separated by cell membrane; when ion channels are opened, ions flow -> generating electrical signals -> so neurons can communicate info through these electrical signals
- neurons generate a constant negative voltage across membrane: the rmp
- an AP abolishes the –ve rmp, making membrane potential transiently positive
- we can record and measure ion currents using electrophysiology
- hyperpolarization is usually the movement of +ve ions moving outward, but it can also be the movement of –ve ions moving inward; while depolarization is the opposite
How do these membrane potentials arise?
- electrical signals are generated through action of ion channels by opening and closing
- the membrane bi-layer is impermeable to ions (polar/hydrophilic faces outward; nonpolar/hydrophobic faces inward)
- ions cross membrane passively through ion channels (movement of ions driven passively by the difference of gradient across membrane); or actively through transport molecules (pumps/transporters)
- both ion channels and transport molecules are membrane-spanning proteins (transmembrane)
General features of an ion channel
- central water-filled pore
-