Chapter 3

Question 1

How does the simple reflex work?

Answer 1

-simple reflex requires complex information processing
-requires collecting, distributing and integrating information rapidly and in parallel

Answer 2

-neuron conducts information over a distance using electrical signals (made of electrically charged ions)
-electrical signal/nerve impulse is called an Action Potential (AP)

Question 3

What stops the electrical signals from disappearing into conductive environment?

Answer 3

-axonal membrane helps prevent these electrical signals from dissipating in a very conductive environment (salty extracellular fluid)

Question 4

What is an Action Potential?

Answer 4

-‘potential’ refers to the separation of electrical charge across the axonal membrane
-APs do not diminish over distance; signals of fixed size and duration

Question 5

How is information encoded?

Answer 5

-frequency of action potentials of individual neurons (more APs = higher intensity)
-distribution and number of neurons firing action potentials

Question 6

When does a cell have an Excitable membrane?

Answer 6

-cell capable of generating and conducting action potentials

Question 7

What is Resting Membrane Potential?

Answer 7

-when a cell with an excitable membrane isn’t generating impulses
-negative electrical charge on the inside compared to the outside
-AP is a brief reversal of this

Answer 8

intracellular fuild (cytosol) and extracellular fluid are made up of water containing ions Na+, K+, Ca2+, Cl-