introduction to neuroscience 1

Nervous System

A complex network of cells that communicate through electrical and chemical signals, organized at multiple levels.

Central Nervous System

Consists of the brain and spinal cord, processing information and coordinating responses.

Peripheral Nervous System

Includes all the nerves that lie outside the central nervous system.

Neuron

Electrically excitable cells that are the fundamental building blocks of the nervous system.

Dendrites

Branches of a neuron that receive synaptic input from axon terminals.

Cell Body/Soma

The part of a neuron responsible for protein synthesis and initiating electrical impulses.

Axon

A part of the neuron that sends output signals to other neurons.

Myelin

A fatty substance that insulates axons, allowing faster signal transmission.

Nodes of Ranvier

Gaps in myelin sheath where the signal is regenerated, boosting the signal.

Synapse

The junction between two neurons, where neurotransmitters are released to transmit signals.

Astrocytes

Support cells in the nervous system that contribute to the formation of the blood-brain barrier.

Oligodendrocytes

Support cells that produce myelin in the central nervous system.

Schwann Cells

Support cells that provide myelin in the peripheral nervous system.

Gray Matter

Part of the nervous system containing cell bodies and unmyelinated axons.

White Matter

Part of the nervous system made up of myelinated axons.

Frontal Lobe

Region of the brain important for executing functions and motor control, such as speech production.

Temporal Lobe

Region of the brain important for memory, hearing, and speech comprehension.

Hyrppolarization

A phase during an action potential when the membrane potential becomes more negative than the resting potential.

Ion Channels

Proteins that allow ions to diffuse across the plasma membrane, regulating ion concentration.

Sodium-Potassium Pump

A protein that actively transports sodium out of and potassium into the cell, maintaining membrane potential.

Action Potential

A rapid change in membrane potential that occurs when a neuron sends a signal.

What does the voltage clamp method do

Allows us to examine the current across the membrane

Passive current flow

Negative that the cells are hypolavising, pulls current down so it can reach threshold

Active current flow

Pushes the membrane against threshold - will allow neurons to fire

Electrochemical equilibrium

Process of moving its in and out of the concentration gradient

Myleination

Increases the speed that action potential propagate

What is depolarization

Occurs when the membrane potential becomes less negative

Which ligand-gated ion channel is regulated primarily by an intracellular signet

The camp - and c GMP gated ion channels

The TRP ion channel family includes channels responsive to?

Heat and cold

What would occur if the ATPase pumps in a neuron stopped functioning ?

Concentration gradients would not be maintained across the membrane

What is the action potential?

Is an active response generated by the neuron and a brief change in the membrane potential

What is the membrane potential

It is the difference in electrical charge within the outside and inside of a neuron

What is practical about the giant nerve cell of a squid

Practical to exclude the cytoplasm from the giant axon and measure it's ionic composition

Role of refractoriness

Limits the number of action potentials that a neuron can produce per unit of time

What are. the 3 different time-dependant and voltage-sensitive processes for the voltage clamp

1. Activation of NA+ conductance

2. Activation of K+ conductance

3. Inactivation of NA+ conductance

How is the action potential generated

It inserts two electrodes ( the membrane voltage and inject current)

What are the 6 phases of the action potential

1. Resting potential

2. Rising phase

3. Overshoot phase

4. Falling phase

5. Undershoot phase

6. Recovery phase

What does the hydrophobic anterior of the bilayer do ?

Prevents the ions of movement across the membrane( can only pass through specialized channels