Nervous System Flashcards
What is coordination carried out by
Nervous system and endocrine system
What is the nervous system
Allows an organism to respond to stimuli in its internal or external environment
Stimulus
Change in your environment
What are the electrical signals carried out by
Specialised cell neurons
Central nervous system
Brain and spinal cord
Peripheral nervous system
Nerves branching out from the cns to all parts of the body
Receptor
A nerve cell that detects a stimulus
Effector
Muscle/ gland that carries out a Responce
Neuron
A specialized cell that carries electrical messages around the body
Impulse
Electrical message carries by a neuron
Three types of motor neuron
Sensory
Inter
Motor
Sensory neuron Carries messages from
Sense organs to cns
Interneuron connects
Sensory and motor neurons
Interneuron carry messages
Within the cns
Motor neurons carries
Impulses from the cns to muscles and glands
Mitochondria
Produce energy
Cell body contains
Nucleus and mitochondria
Cell body produces
Neurotransmitter chemicals
Dendrite
Short fiber
Receives info and carries it towards the cell body
Axon
Long fiber
Conducts impulses away from the cell body
Short fiber
Dendrite
Long fiber
Axon
Schwann cells form
Myelin sheath
Myelin sheath
Protects the neuron
Neurotransmitter swellings
Release chemicals which carry the impulses from one neuron to the next
Synapse is a region where
Two neurons come into close contact (but don’t touch)
Synaptic cleft
Gal between two neurons
Eg of a neuro transmitter
Acetylcholine
What clears a neurotransmitter from the synaptic cleft
Cholinesterase
Why are neurons not in direct contact at a synapse
To prevent continuous stimulation
How many neurons in the Brain
Over 1 billion
What does the brain protect
Three membranes (meninges) Cerebrospinal fluid
How many pairs of spinal nerves in a spinal cord
33
What does each spinal nerve have
Dorsal and ventral root
Dorsal root consists of
Sensory neurons - carry info to spinal cord
Dorsal root ganglion
Swelling that consists of cell bodies of sensory neurons
Central root consists of
Motor neurons - carry info to spinal cord, muscles and glands
Reflex action
Quick involuntary response to a stimulus
Reflex arc
Pathway the reflex takes
Route taken along the reflex arc
Receptor Sensory neuron Spinal cord Interneuron Motor neuron Effector
Cause of Parkinson’s disease
Failure to produce dopamine
Symptoms of Parkinson’s disease
Trembling hands
What mimics dopamine
Levadopa
