W4 Neurotransmission- Action potential and synaptic transmission Flashcards
How does a membrane become more permeable to ions?
Protein channels in the cell membrane will open
e.g. Voltage gated sodium ion channels for Na+
What is compound action potential? (lab)
Action potentials are generated in individual axons whereas a compound action potential (CAP) is the sum of action potentials recorded between 2 external electrodes.
What is the Somatic nervous system?
(SNS)
What does it consist of?
How does information travel?
The voluntary nervous system.
In this system, information from the periphery travels to the CNS along afferent sensory nerves and responses travel directly to skeletal muscles along effector motor nerves.
Includes Brain, Spinal cord, Neurones, Nerves, Muscle
What does the CNS consist of?
The brain and spinal cord.
What does the Peripheral nervous system consist of?
Sensory nerves
Nerves from spine to muscles
Basic description of a neurone function:
Transmits action potential from dendrite to axon terminal
Many have a lipid sheath called myelin
Neurones form networks
What is a synapse
Where 2 neurones connect
What is glia?
Where are they found?
A type of cell in the PNS and CNS
What is membrane potential (difference) a result of?
Ion gradients
(Ion conc outside vs inside a cell)
An action potential is a form of…
Bioelectricity
In most cells there are more positive ions….. the cell than…. the cell
So there is a negative potential difference
Outside
Inside
(around -70 mV)
What are excitable cells?
Where their membrane potential changes in response to stimuli
e.g. neurons
The cell membrane is highly… to ions
impermeable- ions can’t cross it easily
(more on outside)
What does the Membrane potential allow?
Electrical signalling and excitability
What are the types of transport across cell membranes
Passive diffusion
Facilitated diffusion
Active transport
Osmosis
What is transported during passive diffusion?
Ethanol, O2, CO2, weak acids and bases