Introduction/Revision Flashcards
What is the nervous system responsible for?
Control of homeostasis
Control of subconscious body functions
Thoughts, feelings, memories, emotions
Creating sensations and perceptions from sensory information: vision, hearing, taste, smell, touch etc
Pain
Movements and behaviours, voluntary and innate
Reproductive function
What are the two divisions of the nervous system?
(1) Central Nervous System (CNS)
(2) Peripheral Nervous System (PNS)
What does the CNS consist of?
Brain and Spinal Cord
What two general cell classes make up nervous system?
Neurons and glia
What is Glia?
Support cells
What does the PNS consist of?
Peripheral nerves and ganglia
What are ganglia?
A collection of cell bodies
What does the CNS do?
Receives, processes and responses to sensory information
What does the PNS do?
Takes information to and from the CNS
What is the input zone of neuron’s?
Dendrites and cell body (receive chemical signals)
What is the summation zone of neuron?
Axon hillock (summates the inputs - if the summation of inputs reach threshold then it is in the axon hillock that AP is generated).
What is the conduction zone of neuron?
Axon (various lengths)
Axon carries electrical signals between brain areas, to and from spinal cord, or from peripheral sensory receptors and to effector cells).
What is the output zone of neuron?
Axon terminals (which are in contact with input zone of other neuron’s or effectors)
Axon terminals release neurotransmitters (which re chemical signals).
What are the four morphological types of neurons and their structure?
multipolar - multiple process emanate from the cell body
bipolar - two processes emanate from the cell body
unipolar - one process emanates from the cell body then branches into dendrite and axon
anaxonic - no distinct axon and all processes look alike
Why do peripheral cells not need their own support cells?
Because they get their nutrients from fluid.
Important to note there are PNS support cells though.
What are the key glia (support cells) in the CNS and what support do they provide?
Oligodendrocytes (form the myelin sheath)
Astrocytes (provide nutrients, maintain extracellular environment, and provide structural support).
Microglia (mount the immune repsonse)
Ependymal Cells (circulate and produce cerebrospinal fluid)
What are the PNS glia (support cells)?
Schwann cells (form the myelin sheath)
Satellite cells (provide nutrients and structural support to neurons).
What is the effect of saltatory conduction?
Increases the speed of action potential propagation
What is the gyrus?
The ridges of the brain (pre and post of the central sulcus)
What is the central sulcus?
The groove of the brain
What does the post-central gyrus do?
Control of primary somatosensory cortex
What is the pre-central gyrus?
Control of the primary motor cortex
What does afferent mean?
The information coming into the brain (A=Arriving)
What does efferent mean?
The information going out of the brain (E=Exiting)
What does the somatic nervous system do?
Controls the processes of conscious sensation and voluntary movements.
What does the autonomic nervous system do?
Controls unconscious sensation and involuntary movements.
Consists of both parasympathetic and sympathetic pathways.
What is parasympathetic and what neurotransmitters does it use?
The division of autonomic nervous system that drives the restful ‘rest and digest’ situations.
Uses acetylcholine between both the pre and post ganglion.
What is sympathetic?
The division of the autonomic nervous that drives the stressful ‘fight and flight’ situations.
Uses acetylcholine in the pre-ganalionic neuron and noradrenaline in the post-ganglionic neuron.
