L16 (M1) Flashcards
How are memories stored in the brain?
Memories are strengthened connections between neurons
memories are not static, they are consolidated retrieved and then reconsolidated
memories are connections between neurons, what happens between these neurons
- Release of neurotransmitter
- Activation of postsynaptic receptors
- Trafficking of receptors to the PSD
- Local translation of new proteins
- Altered gene expression
what is the process of information transfer at synapses is called
synaptic transmission.
what does synaptic transmission involve
Synaptic transmission involves a change in the membrane potential.
what is the definition of membrane potential
• Definition: electrical potential difference across the membrane
what is the range for RMP
• Sometimes Vm is (at rest (The resting membrane potential)
-65 mV (range −30, −90 mV)
Other times it is not
e.g. during an action potential
What causes the resting membrane potential?
- Phospholipid membrane is impermeable to ions.
2. There is an uneven distribution of ions between inside and outside of the cell
What causes the uneven distribution of ions across the membrane?
Sodium-Potassium Pump
Calcium pump
Additional mechanisms (methods of calcium homeostasis)
what is the role of the Sodium-Potassium Pump
ions
• Is an integral membrane protein
• Concentrates K+ inside the neuron
and Na+ outside
• If Na+ levels are high “inside” the pump breaks down ATP to produce energy
• This drives the pump
• The pump drives ions against their concentration gradients
describe the Ca pump
• Actively transports Ca2+ out of the
cytosol across the cell membrane.
Additional mechanisms methods of
calcium homeostasis include:
• intracellular calcium-binding proteins
and
• organelles (eg endoplasmic reticulum
and mitochondria)
hyperpolarised =
depolerised =
H= inhibited neuron (Influx of -ve ions)
D= excited neuron (Influx of +ve ions)
