Revision Yr 11 Mocks- Homeostasis and Nervous system Flashcards
What is homeostasis
How the body or cells maintain a constant internal environment
E.g body temp
What are the messages in our body sent around as
Electrical impulses
What is a stimulus
A change in the environment, e.g noise
Where are stimuli picked up
In the receptors, in sense organs Eyes Nose Mouth Ears Skin
What do electrical impulses travel through and along
They travel along neurons
What are the three types of neuron
Sensory neurone
Relay neurone
Motor neurone
What it the CNS
The central nervous system, brian or spinal cord
What is a the reflex arc
The pathway the electrical impulses take form a stimuli to a response
What is the pathway of a conscious action
Stimulus Receptor in sense organ Sensory neurone CNS (brain) Relay neurone Motor neurone Effector/muscle/gland Response
What is the reflex arc in a reflex action
Stimulus Receptor in sense organ Sensory neurone CNS (spinal cord) Relay neurone Motor neurone Effector/muscle/gland Response
What is the difference between a reflex and conscious action
A reflex action is faster as it is natural and built in, goes through spinal cord so its quicker
What is a synapse
A synapse is the gap between two neurones
Step by step how does the electrical impulse cross the synapse
(5)
Electrical impulse reaches end of neurone
Stimulates the release of neurotransmitter chemicals
The chemicals diffuse across the synapse
Bind to the receptors in next neurone
Generates new impulse (same message) carries along next neurone
