100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Neurones and Synapses Summary Sheet $3.88
Add to cart

Summary

Neurones and Synapses Summary Sheet

2 reviews
 120 views  0 purchase
  • Course
  • Institution
  • Book

Neurones and Synapses Summary Sheet

Preview 1 out of 4  pages

  • No
  • Neurones and synapses
  • February 26, 2019
  • 4
  • 2018/2019
  • Summary

2  reviews

review-writer-avatar

By: keelymckeown • 2 year ago

review-writer-avatar

By: oisincassidy1 • 3 year ago

avatar-seller
Neurones and Synapses
Neurones:

-Motor Neurones: carry impulses from the CNS( brain or spinal cord) to effectors (muscles and
glands)

-Sensory Neurones: carry impulses from receptors to the CNS

-Connector: (relay, association or intermediate) neurones – connect neurones within the CNS

Function: To conduct nerve impulses

-Nerves are bundles of neurones

Axon: Transmits impulses away from the cell body (in motor neurones entire nerve fibre is an axon)

Dendron: Carries impulses to the cell body

Dendrites: very small extensions that can conduct impulses into a dendron or into the cell body
directly

Synaptic bulbs: Axons terminate in synaptic bulbs

Myelinated: Dendrons and axons are covered with a myelin sheath, (myelin sheath is both protective
and serves to speed up nervous conduction.)

Schwann Cells: forms myelin sheath

Nodes of Ranvier: Small gaps between Schwann Cells in the myelin sheath

The Resting Potential

-The potential difference across the cell surface membranes of neurones, neurones are polarised.

-Excess of positively charged ions (Na+) outside the membrane compared to the inside. At rest,
outside is positive relative to inside, around 70mV potential difference.

-This differential is maintained as the cell surface membrane is largely impermeable to the flow of
sodium ions when not conducting an impulse.

Action Potential

-When a neurone is stimulated the cell surface membrane becomes permeable to ions

 Resting potential with inside of axon -70mV relative to outside.
 Membrane becomes permeable and positive ions diffuse into the axon- starting to become
polarised
 At -55mV gated channels open and positive ions flood in at a rapid rate. Rapid depolarisation
o the membrane takes place. Inside becomes +40mV relative to outside= action potential.
 Positive ions diffuse out and are also pumped out of the axon. Refractory period as the
membrane cannot become polarised again until resting potential is restored. Slight
overshoot at the end, axon membrane becomes slightly more negative than the normal
resting period (hyperpolarisation)
 Resting potential is restored and axon can conduct another nerve impulse if needed.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller TiarnanMcKeever. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $3.88. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

52510 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$3.88
  • (2)
Add to cart
Added