Neurophysiology and Synaptic Mechanisms Flashcards Preview

Advanced Human Physiology > Neurophysiology and Synaptic Mechanisms > Flashcards

Flashcards in Neurophysiology and Synaptic Mechanisms Deck (18)
Loading flashcards...
1
Q

What are the different types of neurons?

A

Projection neurons Local neurons

2
Q

What are the functions of Projection neurons?

A

Collect and collate input locally and from distant projection neurons Send output to distant areas of the brain

3
Q

Give examples of projection neurons

A

Pyramidal cells Stellate cells

4
Q

What are the functions of Local neurons?

A

Collect and collate input locally Send output locally to projection neurons or other local neurons

5
Q

Give an example of a local neuron

A

Interneurons

6
Q

What are the structural features of a neuron?

A

Nucleus Dendrites (Receives afferent signals) Schwann Cells (myelination) Soma (Processes information) Axon Terminal Bouton (forms the synapse)

7
Q

What are the structural features of the soma?

A

Cytosol Nucleus, nucleolus Endoplasmic reticulum (smooth, rough) Golgi apparatus Ribosomes Mitochondria Microtubules

8
Q

What is the function of the soma?

A

Summates input from dendrites to cause output to the axon

9
Q

What are the features of the dendtrites?

A

Multiple projections from the soma The information receivers Receive neurotransmitter input from other neurons (spines increase surface area for input) Express a huge variety of receptors; Ion channels - depolarising, hyperpolarising 2nd messenger systems, modulatory Membrane potential changes transmitted to soma

10
Q

What are the features of the axon?

A

Begins at axon hillock Single projection which may divide Carries output of the neuron in the form of action potentials Voltage gated Na+ channels Several types of K+ channel Microtubules carry vesicles to terminal Axoplasmic transport

11
Q

What are the features of the axon terminal?

A

Enlarged terminal of the axon Contains: Cytosol - Enzymes for neurotransmitter production Organelles - Mitochondria for ATP production - Neurotransmitter vesicles - Microtubules to hold vesicles

12
Q

What is resting membrane potential (Vr)?

A

Typically -65mV in a neuron (compared to ECF)

13
Q

What causes resting membrane potential?

A

Caused by relative permeabilities of ions

14
Q

What is the function of the Nernst Equation?

A

The Nernst Equation enables the determination of cell potential under non-standard conditions.

It calculates the Equilibrium Potential for an ion

•The Vm at which the ion will not flow

15
Q

What is the Nernst Equation?

A

Eion = 61.5 log [ion]o / [ion]i

(at 37oC, for monovalent cation)

16
Q

What is function of the Goldman Equation?

A

The Goldman equation is used in cell membrane physiology to determine the reversal potential across a cell’s membrane, taking into account all of the ions that are permeant through that membrane.

Combines Nernst equations to give Vm

17
Q

What is the Goldman equation?

A
18
Q

What does membrane potential (Vm) depend on?

A

Concentrations of ion inside and outside the cell

Relative permeabilities of the membrane to those ions