Neuroscience Flashcards
How many connections does the average neurons make?
•1,000 connections
Name Neuronal cell properties
- Excitability
- Conductivity
- Secretion
What are the features of a resting neurone? - Mention membrane
- The membrane itself is relatively impermeable to ions
- Inside of membrane has a negative charge with respect to the outside
The equilibrium potential of an ion is the point at which there would be….
• no net movement of the ion across the membrane
The membrane at rest has a potential of….
70mV
For the membrane at rest, what are the sodium potassium channels doing?
- They are closed
At the local potential the membrane potential…..
• Rises
What happens if the local potential doesn’t reach the threshold?
- Will diminish without causing an action potential
If they do reach the threshold an action potential will occur
Once the membrane has reached the depolarisation stage it reaches the T_____ potential and rises R_____
• Threshold
• Rapidly
(Potassium channels remain closed)
At the state of repolarisation has peaked and falls back towards…..
• resting potential
(voltage gated sodium channels inactivated - not closed)
~ Voltage gated potassium channels open
The absolute refractory period is impossible to…..
- Fire another action potential
Potassium channels closing, but sodium channels inactivated
True or False
- The relative refractory period is possible to fire another action potential, but a larger stimulus is required
True
• Potassium channels closing, sodium channels de-inactivated
• Sodium/Potassium pump restores ion balance
Which zone is the action potential generated in?
- The trigger zone
Along axons what do the propagate carry?
- Carry sensory or motor information to the appropriate location
Myeloma room is where the…..
- Neurone is insulated which allows more rapid conduction of the action potential (Different types of neurones may be myelinated or unmyelinated)
What is the progress of the action potential along an unmyelinated axons called?
- Continuous propagation
What is the progress of action potentials along myelinated axons called?
- Saltatory propagation
Areas without myelin are called Nodes or Ranvier
Schwann cells myelinate……
- Peripheral axons
Oligodendrocytes myelinate…..
- CNS axons
What is multiple sclerosis (MS)?
- Autoimmune disorder when myelination of central nerves is targeted
What is guillain-Barré syndrome?
- Autoimmune disorder when myelination of peripheral nerves is targeted
Where do neurones communicate with one another?
• At synapses
~ Synaptic transmission can be electrical or chemical
REVISE SYNAPTIC TRANSMISSION
REVISE SYNAPTIC TRANSMISSION
State key neurotransmitters
- Adrenaline
- Serotonin
- Dopamine
Name the main processes in the regulation of different transmitter systems
1) synthesis
2) storage
3) release
4) receptor binding
5) inactivation/reuptake
An excitatory neutron may activate an _______ neurone, which may in turn inhibit the ______ excitatory neutron
- Inhibitory
- Excitatory
What is an agonist?
• Chemical that binds to receptor which activates the receptor to produce a molecular/ cellular response
Compare a Full; Partial & Inverse agonist
- Full: produces complete molecular response
- Partial: interacts with receptor in an inefficient manner producing less than maximal molecular response
- Inverse: binds to spontaneously activated receptor leading to deactivation of the receptor
What is an antagonist?
- A chemical that interacts with a receptor to inhibit the action of an agonist
Give an example of a drug that alters receptor activity
- Nicotine
Cocaine blocks ……
- Dopamine transporters
Temporal Vs spatial summation
Temporal: Single synapse
Spatial: Many synapses
GLIA
GLIA
What does the CNS and PNS consist off?
- CNS: brain and spinal cord
* PNS: everything outside the brain and spinal cord
What does the PNS include? (What type of nerves)
- Sensory
- Motor
What is the somatic nervous system responsible for?
• Voluntary movement
What is the autonomic nervous system responsible for?
- Responsible for regulating involuntary mechanisms (e.g heart rate)
What are the two branches or the autonomic nervous system?
- Sympathetic nervous system
* Parasympathetic nervous system
What system specifically regulates the gastrointestinal tract?
• Enteric nervous system
The sympathetic system has increased metabolic rate, heart rate compared to the parasympathetic nervous system which…..
- Has a decreased metabolic rate, heart rate
In the brain the cerebrum is responsible for…..
- Higher brain functions
In the brain the diencephalon is responsible for…..
- Lower brain functions
The spinal cord is responsible for….
- Reflex actions
How many lobes is the brain split into and what are these?
4 lobes • frontal lobe • temporal lobe • parietal lobe • occipital lobe
In the brain what is white matter?
•Axons
