Neuroscience: Electrical Synapses

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of neuroglia cells?

Synthesizing neurotransmitters

Support, nourish, and protect neurons (correct)

Maintaining homeostasis in the nervous system

Sensing, thinking, and muscle activity control

Neurons are not electrically excitable.

False

What is the role of Nissl bodies in neurons?

protein synthesis

Neurotransmitters are synthesized in the ____________________ and stored in the synaptic end bulb.

cell body Signup and view all the answers

Match the following cellular components with their functions:

Neurons = Sensing, thinking, and muscle activity control Neuroglia = Support, nourish, and protect neurons Nissl bodies = Essential for protein synthesis Signup and view all the answers

Neurotransmitters are not synthesized in the cell body.

False Signup and view all the answers

What is the primary function of action potentials in neurons?

Communication over long distances Signup and view all the answers

Leakage channels in neurons are always open.

False Signup and view all the answers

What type of channels respond to chemical stimuli in neurons?

Ligand-gated channels Signup and view all the answers

White matter primarily consists of ____________________ axons.

myelinated Signup and view all the answers

Match the following types of ion channels with their characteristics:

Leakage channels = Alternate between open and closed K+ channels = More numerous than Na+ channels Ligand-gated channels = Respond to chemical stimuli Signup and view all the answers

What is the direction of ion movement across the membrane via chemical gradient?

From high to low Signup and view all the answers

Grey matter contains myelinated axons.

False Signup and view all the answers

What is the effect of ions flowing across the membrane?

Electrical current is created that can alter membrane potential (MP) Signup and view all the answers

What is the primary function of gap junctions in electrical synapses?

To act as a tunnel between the cytosol of two cells Signup and view all the answers

Chemical synapses have a faster communication speed compared to electrical synapses.

False Signup and view all the answers

What is the effect of excitatory postsynaptic potentials (EPSP) on the postsynaptic neuron?

A depolarizing postsynaptic potential Signup and view all the answers

The synaptic delay at a chemical synapse is approximately _______ msec.

0.5 Signup and view all the answers

Match the following types of postsynaptic potentials with their effects on the postsynaptic neuron:

EPSP = Depolarizing IPSP = Hyperpolarizing Signup and view all the answers

What is the function of neurotransmitters in chemical synapses?

To bind to receptors in the postsynaptic neuron Signup and view all the answers

A postsynaptic neuron can only receive one signal at a time.

False Signup and view all the answers

What is the advantage of electrical synapses in terms of neuronal communication?

Faster communication and synchronisation Signup and view all the answers

Study Notes

Electrical Synapses

Action potentials (AP) conduct between cells via gap junctions
Gap junctions contain tubular connexons, acting like tunnels between the cytosol of two cells
Ions flow through connexons, spreading AP
Advantages:
- Faster communication
- Synchronization of a group of neurons or muscle fibers

Chemical Synapses

Plasma membranes are separated by synaptic cleft
Presynaptic neuron releases neurotransmitters (NT) into synaptic cleft
NT binds to receptors in postsynaptic neuron, resulting in postsynaptic potential
Electrical signal converted to chemical signal, leading to an electrical signal
Synaptic delay of 0.5 msec

Synapses Between Neurons

Postsynaptic potentials:
- Excitatory postsynaptic potentials (EPSP): depolarizing postsynaptic potential
- Inhibitory postsynaptic potentials (IPSP): hyperpolarizing postsynaptic potential
A postsynaptic neuron can receive many signals at once

White and Grey Matter

White matter consists of myelinated axons
Grey matter contains everything else, like dendrites, cell bodies, etc.

Electrical Signals in Neurons

Excitable cells communicate via:
- Action potentials: allow communication over short and long distances
- Graded potentials: allow communication over short distances

Ion Channels

Allow movement of specific ions across the membrane via chemical gradient
Move from high to low concentration
Cation move to anionic environment and vice versa
As ions flow, electrical current created that can alter membrane potential (MP)

Ion Channels in Neurons

Leakage channels alternate between open and closed
K+ channels are more numerous than Na+ channels
Ligand-gated channels respond to chemical stimuli
Located along the dendrites, participating in producing graded potential

Histology of the Nervous System

2 cell types:
- Neurons: sensing, thinking, memory, muscle activity control, gland secretion
- Neuroglia: support, nourish, protect neurons, maintain homeostasis in interstitial fluid

Neurons

Electrically excitable
Neurotransmitters synthesized in the cell body and stored in the synaptic end bulb
Essential for protein synthesis (nissl bodies)

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Understand how electrical synapses work through gap junctions, allowing ions to flow and spread action potential between cells, enabling faster communication and synchronization.