AOS 1; NERVOUS SYSTEM FUNCTIONING DOT POINTS 1-5 Flashcards
How is the nervous system split up?
the nervous system is firstly split into the CNS and PNS. The CNS is composed of the brain and spinal cord. The PNS system is further split into the autonomic and somatic nervous system. The autonomic nervous system is then split into the parasympathetic and sympathetic nervous system.
Name the three types of neurons found in the nervous system
Sensory, Motor and Interneurons
What is the main role of motor neurons?
Are responsible for carry information from the CNS to glands, muscles and organs in the PNS
If a message is being sent to Organs, glands or muscles from the CNS which tract would it use?
Efferent
Which neuron is responsible for linking the communication of motor and sensory neurons?
Interneurons
What are sensory neurons responsible for?
Carrying information from sensory organs to the CNS
What messages are sent via afferent tracts?
Sensory messages
What are the main functions of the Brain?
- Regulate and guid all aspects of the Nervous system
- Regulate vital boy functions
- Origina of emotions and personality
- Responsible for receiving info from outside world and co-ordinating it
What is the spinal cord responsible for?
Passing sensory information from the PNS to the CNS and vice versa.
Describe the PNS
The PNS is the complete network of nerves outside of the PNS. It consists of muscles, glands and organs.
What are the two section of the PNS?
Autonomic and Somatic nervous systems
What is the main role of the Somatic nervous system?
The control of conscious movement
What is the main role of the Autonomic nervous system?
is responsible for the bodies involuntary functions such as breathing and blinking. They are processes which occur unconsciously
What are the names of the two sub components which make up the ANS?
The parasympathetic and sympathetic nervous system
What is the role of the parasympathetic nervous system?
The parasympathetic nervous system calms our body down, bringing it back to s state of homeostasis [the stable maintenance and regulation of internal body functions.]
What is the main role of the sympathetic nervous system?
The parasympathetic nervous system is our bodies stress response and is equivalent to our flight, fight or freeze response. can increase adrenaline, dilate pupils and shut down digestion
Define conscious
A process which is voluntary, controlled and usually complex. It s an action that we are aware of and have chosen to do
Define unconscious
Is a process which is involuntary and does not involve our awareness. They are simple actions which are automatic, innate and not learnt.
What is a spinal reflex?
An unconscious, involuntary and automatically occurring response to stimuli without any involvement of the brain.
Explain the involvement of the brain in spinal reflex
Although the brain is not involved with the immediate reaction the message still continues to the brain so that we can remember the experience.
Why do we have spinal reflexes?
Spinal reflexes enable faster reactions to dangerous situations ad are an adaptive response to increase and organisms chance of survival.
Why is the spinal cord designed as a two way highway?
This design helps enable a faster neural transmission by creating streamlined pathways.
Describe the spinal cord
A cable like column of nerve fibres which extends from the base of the brain to the lower back.
What is the role of the spinal cord?
To pass information from the PNS to the CNS and information from the CNS to the PNS.
Describe the process of neural communication
Neural communication is an electrochemical process
What is the role of neurons?
To communicate messages
Can neurons adapt physically? Explain.
Yes they can adapt physically. This allows the neurons physical adapt to suit any frequency or speed required. This is why we get better at things when we practice.
Define Neuron
Neurons are the basic building blocks of the nervous system and are specialised to communicate.
Describe the function of dendrites
Dendrites are swindle buts which receive incoming information
Describe the function of the Nucleus
The nucleus is responsible for all cell functions and the maintenance of the cell
Describe the function of myelin sheath
Myelin sheath is a fatty tissue which surrounds the axon. It acts as an insulator, speeding up the transmission of neural messages
Describe the function of Axon terminals
Axon terminals are where the electrical messages is converted by the terminal buttons into a chemical message so it can be sent through the synapse to the next cell
What is the role of the interneuron?
The interneuron is are where sensory information is processed for an accurate response. It is the communicator between sensory and motor neruons
What is action potential?
Action potential describes the change of charges which occur as the neural message passes through the axon. In neurones the negative ions within the axon become positive as the message passes through therefor the ions outside must change to negative.
What is resting potential?
Resting potential is when the cell is waiting for a message to be received. A neutrons resting state is when the ions within the axon are negative and the ions surrounding the axon are positive.
What processes is used to communicate between neurones?
Chemical energy
Explain what happens when the electrical impulse reaches the end of the neuron
When the electrical message reaches the axon terminals it is covered into chemicals known as neurotransmitters which are then released from the terminal buttons across the synapse to the receptor sites at the post synaptic nerve.
Define neurotransmitter
neurotransmitters are a chemical messenger synthesised within the pre synaptic neuron.
What are excitatory transmitters?
Neurotransmitters which stimulates or activates post synaptic neurons to fire
What are inhibitory neurotransmitters?
are neurotransmitters which block or prevent the post synaptic neuron from firing.
What is the main excitatory neurotransmitter?
glutamate, which is involved in learning and memory
What is the main inhibitory neurotransmitter?
GABA, which is involves in anxiety levels and motor control
What is Parkinson’s disease?
PD is a neurodegenerative disease, which is a disease which gradually and progressively kills nerve cells, leading to permanent loss and dysfunction is the NS.
At what age does Parkinson’s usually occur?
60-65
What are the causes?
Although the cause is unknown, it is known that it begins with the deterioration of nerves in the substantia nigra impairing the production of dopamine.
What is the main neurotransmitter associated with PD?
dopamine
What is the function of dopamine?
is a neuron transmitter which is involved in the transmission of impulses to co-ordinate smooth movements
What are the main motor symptoms of PD?
- difficulty controlling voluntary movement
- Bradykinesia ( slowness and difficulty initiating voluntary actions)
- restless leg syndrome
- freezing gait
List some non motor symptoms of PD
- mental health
- cognitive impairment
- decreased sense of smell
Role of the brain in the NS?
- regulates and guides all aspects of the nervous system
- origin of emotions and personality
- receives and coordinates information from the outside world.
Define agonist
artificial chemicals which replaces a neurotransmitter or increases its presence therefor imitating the action of the neurotransmitter
Define antagonist
the use of an artificial chemical to inhibit the release of a neurotransmitter or block the receptor sites which make the post septic neutron less likely to fire
