Sense & React
What do we call any internal or external change detected by the body?
A stimulus
Neurons are the building blocks of this system
Nervous system
The two main divisions of the nervous system.
Central nervous system (CNS) and peripheral nervous system (PNS)
This neurodegenerative disease causes memory loss, disorientation and language problems. Age is the main risk factor.
Alzheimer's Disease
True or false: the widest nerve in the body is as thick as your thumb
True — the sciatic nerve is about 1.5 cm in diameter
These are our sense organs — they detect stimuli and pass on information.
Receptors (ex: eyes, ears)
The three main structural parts of every neuron
Cell body (soma), axon, and dendrites
Three membranes that wrap the brain and spinal cord and protect against bacteria
The meninges (dura mater, arachnoid mater, pia mater)
This nervous system condition causes sudden violent shaking and loss of consciousness.
Epilepsy
This Spanish scientist compared brain activity to muscular exercise, arguing the brain gets stronger with use.
Ramón y Cajal
The four-step chain from detecting a change to reacting to it.
The stimulus-response mechanism
This type of neuron connects sensory neurons with motor neurons
Interneurons
An insulating fatty layer around axons that speeds up nerve impulse transmission.
The myelin sheath
Name two healthy habits that protect your nervous system.
regular sleep, no recreational drugs, mental exercise, balanced diet, physical exercise, social connection, avoiding chronic stress
this fluid sits between the meninges and acts as a cushion against impacts.
Cerebrospinal fluid
After receptors detect a stimulus, information is sent here to be interpreted before orders are sent to the effectors.
The coordination centres (the brain and spinal cord / CNS)
The tiny space between two neurons where chemical signals must cross.
The synaptic gap
The three types of nerves classified by the fibres they contain.
Sensory nerves, motor nerves, and mixed nerves
In this disease, the patient's own immune system attacks and damages the myelin sheaths
Multiple sclerosis (MS)
Which processes information and which transmits signals: grey matter or white matter?
Grey matter processes info (cell bodies + dendrites); white matter transmits signals (myelinated axons)