Organisation Of Nervous System Flashcards
In which two main categories is the Nervous system divided?
Into the Central Nervous System and the Periphal Nervous System.
How is the Central Nervous System divided?
Into the brain and the Spinal cord.
How is the Periphal Nervous System divided?
Into the Somatic nervous system and the autonomic nervous system.
Which nervous system has sensory and motor pathways and controls muscles and movements?
The somatic nervous system.
Which nervous system has only motor pathways and controls muscles and movements?
The autonomic nervous system.
Which nervous system is responsible for voluntary movements?
The somatic nervous system.
Which nervous system is responsible for involuntary movements such as breathing and heart beat?
The autonomic nervous system.
What do the afferents nerves of the peripheral nervous system do?
The afferent nerves (sensory system)
convey information from the receptors to the central nervous system.
What do the efferent nerves of the peripheral nervous system do?
The efferent nerves (motor system) convey information from the central nervous system to the muscles and glands.
What does the somatic nervous system of the peripheral nervous system’s efferent (motor) system do?
The somatic nervous system (SNS)
conveys information from the central nervous system to skeletal muscles.
What does the autonomic nervous system of the peripheral nervous system’s efferent (motor) system do?
The autonomic nervous system (ANS) conveys information from the central nervous system to smooth muscle, cardiac muscle and glands.
How can the autonomic nervous system (ANS) of the peripheral nervous system be further divided?
Into the sympathetic and parasympathetic nervous system.
What does the sympathetic nervous system of the ANS do?
It controls the body’s response to perceived threats (fight or flight).
It releases adrenaline, increases heart rate, increases conversion of glycogen to glucose, dilates bronchial tubes and pupils, contracts muscles and decreases digestive function, saliva production, mucus production and urine secretion.
What does the parasympathetic nervous system of the ANS do?
The PSNS maintains the body’s internal environment (rest and digest) and is responsible for regulating digestive and sexual functions and while keeping heart rate and blood pressure steady.
What is the main function of our specialised sensory receptors ?
To convert external stimuli into pattern of nerve impulses.
What is a synapse?
The gap between the axon of one neuron and the cell body of the next neuron.
How get information transferred between Neurons?
Electrical impulses carried along the axon stimulate release of neurotransmitters into the synapse, which can trigger an action potential in the next neuron by combining with receptors.
(Chemical transmission, neurotransmitters must be sufficient to activate postsynaptic membrane)
How can synapses vary?
Synapses can be inhibitory as well as excitatory, and activity in the brain is the result of this balance between excitation and inhibition.
How many neurotransmitters are there?
20-30 neurotransmitters, each is associated with a specialised receptor, and there are also enzymes which break down neurotransmitters after their synaptic action.
How are drugs called that are increasing neurotransmitter function?
Agonists
How are drugs called that decrease neurotransmitter function?
Antagonists / Blockers
How do many drugs affect the brain and behaviour?
By interfering with synaptic transmission. Either directly via action on receptors, or indirectly through actions on neurotransmitter release and break down.
What are neuronal pathways?
Some Neurons are organised as pathways running from hindbrain to forebrain , with all Neurons releasing the same neurotransmitter.
The degeneration of which pathway is responsible for symptoms of Parkinson’s disease?
Nigro-striatal dopamine pathway.
