Nervous System Flashcards
Unit 3 Area of Study 1
What is the brain?
A highly complex organ contained within the skull that coordinates mental processes and behaviour, and regulates bodily activity.
What is the spinal cord?
A long, thin bundle of nerves that extends from the base of the brain to the lower back.
What does the sympathetic nervous system do?
Activates internal muscles, organs and glands to prepare the body for vigorous activity or to confront or flee a stressful/ threatening situation.
What does the parasympathetic nervous system do?
Helps to maintain the internal body environment in a steady, balanced state of normal functioning (homeostasis) in times of minimal stress and in the absence of threat.
What is a neuron?
A nerve cell that receives and transmits neural information.
What are motor neurons?
Also known as efferent neurons, they transmit neural messages about motor movement from the CNS to the PNS.
What are sensory neurons?
Also known as afferent neurons, they transmit neural messages about bodily sensations from the PNS to the CNS.
What are interneurons?
They transfer neural messages between sensory neurons and motor neurons and are part of the CNS, including the brain and spinal cord.
What is a conscious response?
A reaction that involves awareness to external and internal stimuli.
What is an unconscious response?
A reaction that does not involve conscious awareness.
What is a spinal reflex?
An unconscious and automatically occurring response to certain stimuli without any involvement of the brain.
What are neurochemicals?
Chemical substances that transmit neural information.
What are neurotransmitters?
Chemical molecules that have an effect on one or two postsynaptic neurons.
What do excitatory neurotransmitters do?
Stimulate postsynaptic neurons to perform their functions, increasing the likelihood of firing an action potential (AP).
What do inhibitory neurotransmitters do?
Block, prevent, or suppress postsynaptic neurons from firing an action potential (AP).
What are neuromodulators?
Chemical molecules that have an effect on multiple postsynaptic neurons.
What is synaptic plasticity?
The ability of synaptic connections to change over time in response to activity or experience/learning.
What is sprouting?
The ability of dendrites or axons to develop new extensions or branches.
What is re-routing?
The ability of a neuron that is connected to a damaged neuron to create an alternative synaptic connection with an undamaged neuron.
What is pruning?
The elimination of synaptic connections that are not adequately activated or ineffective/weak/unused.
What is long-term potentiation?
The long-lasting strengthening of synaptic connections due to repeated stimulation of neural pathways, resulting in enhanced functioning.
What is long-term depression?
The long-lasting decrease in the strength of neural pathways which results from prolonged and repeated low level stimulation or a lack of stimulation.
