Topic 6B - Nervous Coordination

Question 1

Describe the structure of a typical neurone that explains how they are adapted to carry electrochemical signals (electrical impulses)

Answer 1

Myelinated neurone = myelin sheath, which is a fatty, insulating layer made up of Schwann cells (provide protection) to stop electrical impulses being carried to other nearby neurones along the axon.
Long dendrons into dendrites to cell body, connected to other neurones.
Presence of Nodes of Ranvier aid in saltarary Conduction

Question 2

Many neurones have voltage - gated channels, meaning

Answer 2

they only open when surrounding membrane depolarises

Question 3

resting potential

Answer 3

more relatively negative inside cell (due to more positive ions on the outside) - membrane POLARISED (-70mV); potential difference across membrane; when neurone the not stimulated

Question 4

does maintaining the resting potential require ATP?
- side task to think why resting potential is so important

Answer 4

Yes, the sodium - potassium pump is a carrier protein that requires ATP from respiration to release energy

Question 5

SOPI

Answer 5

3 sodium out, 2 potassium in
- results in more sodium ions outside than the amount inside (potassium only 2), overall bigger + charge outside