PSC 101 Lesson 1

What is the primary function of neurons?

Neurons are specialized for communication, collecting information from other cells and sending it to other cells using chemical and electrical signals.

What are the main structures of a typical neuron?

Dendrites, cell body (soma), axon hillock, axon, and synaptic terminal.

What is the role of dendrites in a neuron?

Dendrites are specialized structures for collecting information from other cells.

What is the function of the cell body (soma) in a neuron?

The cell body contains organelles necessary for the cell's function and survival, including the nucleus and mitochondria.

What is the axon hillock?

The axon hillock is the part of the cell body that connects to the axon and is the starting location of action potentials.

What is the function of the axon?

The axon is a long tube through which electrical currents (action potentials) travel from the cell body to the synaptic terminal.

What is the synaptic terminal?

The synaptic terminal (axon bouton) is the end of the axon where it meets its target, usually a dendrite, and is involved in chemical signaling.

What is myelin and its function on axons?

Myelin is a fatty substance that insulates axons, speeding up the transmission of electrical signals.

What might a person with a demyelination disease like MS experience?

They may experience slowed or disrupted communication between neurons, leading to various neurological symptoms.

What are glial cells and their significance?

Glial cells support neurons and are more than just the 'glue' of the nervous system; they play crucial roles in maintaining homeostasis, forming myelin, and providing support and protection.

What is a neural network?

A neural network is a system of interconnected neurons that work together to process complex information.

How do neurons contribute to complex processes like memory and cognition?

Neurons work together in networks to communicate and process information, enabling complex functions such as memory, sensory perception, and cognition.

What are dendritic spines?

Dendritic spines are tiny structures on dendrites that allow a single axon to connect to them, facilitating synaptic transmission.

What is the significance of the nucleus in the neuron?

The nucleus is crucial for gene expression and protein production, which are essential for the neuron's function.

What is the range of axon lengths?

Axons can vary in length from approximately 3 micrometers to over 1 meter.

What happens at the synapse?

At the synapse, chemical signals from the presynaptic axon are received by the postsynaptic dendrites, causing changes in the postsynaptic cell.

Why can't a single neuron perform complex processes alone?

A single neuron cannot perform complex processes like conscious thought or memory recall; it requires the collaboration of many neurons.

What is the importance of mass communication among neurons?

Mass communication among neurons allows the brain to perform complex processes and functions.

What is the role of action potentials in neurons?

Action potentials are electrical impulses that travel along the axon, facilitating communication between neurons.

What is the function of neurotransmitters?

Neurotransmitters are chemicals released at the synaptic terminal that transmit signals between neurons.

What is the purpose of the self-assessment sketch of a neuron?

The sketch helps students practice identifying and labeling the structures of a neuron, reinforcing their understanding of neuron anatomy.

How does the morphology of neurons vary?

Neurons exhibit diverse morphology, reflecting their specialized functions, but share foundational similarities in structure.

What is the significance of the axon in transmitting information?

The axon serves as the pathway for action potentials, allowing information to be transmitted over long distances.

What is the primary function of myelin on axons?

To provide insulation that allows action potentials (APs) to travel farther and faster along long axons.

What happens to action potentials in longer axons without myelin?

They may dissipate before reaching the end of the axon.

What are the Nodes of Ranvier?

Small areas of exposed axon between segments of myelin that are important for action potential travel.

What is the difference between white matter and gray matter?

White matter contains densely packed axons wrapped in myelin, while gray matter consists of cell bodies and dendrites with little to no myelin.

What is multiple sclerosis (MS)?

A disorder that progressively destroys myelin in the central nervous system (CNS), affecting the transmission of action potentials.

What are some common symptoms of multiple sclerosis?

Muscle weakness, vision issues, loss of sensation, and tremors.

What role do glial cells play in the nervous system?

They support neurons and are essential for the overall function of the nervous system.

Why were glial cells historically thought to be just 'glue'?

They were believed to only provide structural support for neurons, but recent research shows they have many important functions.

What metaphor is used to describe the relationship between neurons and glial cells?

Neurons are like Formula 1 racecar drivers, while glial cells are like the pit crew that supports them.

What are astrocytes?

A type of glial cell that delivers energy to neurons, clears excess neurotransmitters, and provides structural support.

What is the blood-brain barrier?

A barrier formed by astrocytes that filters blood contents before they reach neurons, allowing good substances in and blocking harmful ones.

What are the two types of myelinating glia?

Oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS).

What are microglia?

The immune cells of the nervous system that clear debris, destroy invaders, and support healing, but are not technically classified as glia.

How do glial cells contribute to neuron function?

They provide essential support, allowing neurons to focus on communication and processing information.

What recent findings highlight the importance of glial cells?

Current research is uncovering their critical roles in how the nervous system functions beyond just being supportive 'glue'.

What is the significance of myelin in terms of electrical properties?

Myelin reduces charge dissipation, allowing for more efficient and rapid transmission of electrical signals along axons.

What symptoms might a person with MS experience due to myelin destruction?

Symptoms may include muscle weakness, vision problems, loss of sensation, and tremors due to impaired action potential transmission.

What is the role of glial cells in synaptic formation?

Glial cells, particularly astrocytes, promote synaptic formation and help maintain synaptic health.

What happens to the nervous system's function when glial cells are compromised?

The overall function of the nervous system may be impaired, affecting neuronal communication and health.

How do glial cells work together?

They collaborate as a team to support neurons and ensure proper functioning of the nervous system.

What is the impact of myelin loss on action potential propagation?

Loss of myelin can lead to slower and less reliable action potential propagation, resulting in neurological symptoms.

What is the primary focus of current research on glial cells?

To understand their diverse functions and importance in the nervous system beyond structural support.