The nervous system

what is the nervous system

it enables people to react to their surroundings

what 2 main parts are part of the nervous system

the spinal chord and the brain

what is a connection of neurons called

a nerve

What types of neurons are there

• sensory neurons

• relay neurons

• motor neurons

What is the reflex arc

Stimulus →receptor →sensory neurons→synapse→CNS→relay neuron→CNS→synapse→motor neuron→effectors→response

words used to describe a relex

• instantaneous

• usually to protect us

• reduce tissue damage

• they don’t involve the conscious part of the brain

what can affect reaction time

• age

• amount of caffeine/sugar

• number of hours awake

• using your dominant or non-dominant hand

• if you have had alcohol/drugs

• if you have practised the reaction

What is a synapse

A synapse is a gap between 2 neurons

How is the impulse passed

• becomes chemical signals

• 1st neuron releases vesicles (small bubbles)

• vesicles diffuse across the gap

• the vesicles bind to a receptor on the next neuron