The Central Nervous System Flashcards
What does vestigial mean?
The retention of genetically determined attributes that have lost some of their function.
E.g. eyebrow flashing - completely unconscious & indicates a desire for social contact.
What are the subdivisions of the nervous system?
Central nervous system
Peripheral nervous system
What are the subdivisions of the central nervous system?
Brain
Spinal cord
What are the subdivisions of the peripheral nervous system?
Autonomic NS
Somatic NS
What are the subdivisions of the autonomic nervous system?
Sympathetic NS
Parasympathetic NS
What are the subdivisions of the somatic NS?
Sensory neurones
Motor neurones
What are dendrites?
Where the neurone receives electrochemical input from other neurones.
Critical in integrating synaptic inputs and determining action potentials produced by the brain.
What is the role of the axon?
It carries input away from the neurone and transmits information to other neurones
What is the myelin sheath?
Insulates the axon.
Increases the rate at which electrochemical signals pass down the axon.
Why are the nodes of ranvier important?
They allow the electrical impulse to move quickly down the axon.
Why are synapses useful?
Allows a neurone to communicate its electrochemical signal to a neurone via the dendrites.
What is the role of neuroglia cells?
Provides and controls nutrients and chemicals to neurones.
Insulates neurones from each other avoiding electrochemical messages being disrupted.
Why are astrocytes important?
Responsible for forming the blood-brain barrier and providing neurones with nutrients.
Why are oligodendrocytes important?
Cells that form the myelin sheath which are found exclusively in the CNS.
What are unipolar neurones?
Only one neurite extends from the soma.
What are bipolar neurones?
Has two neurites, are usually specialised for sense.
What are multipolar neurones?
A single axon but many dendrites.
What are the roles of each part of the brain:
Corpus Callosum?
Fibres passing between two hemispheres.
Thalamus?
Sensory information
Hypothalamus?
Biological needs e.g. thirst, hunger etc.
Pituitary gland?
‘Master’ gland for endocrine glands
Cerebrum?
Thinking, emotion etc.
Cerebellum
Coordinates muscle movement
Hippocampus?
Learning, memory etc.
Amygdala?
Emotion, aggression etc.
Medulla?
Vital functions
Motor cortex?
Include where it’s situated.
Voluntary movements
Frontal lobe
Sensory cortex?
Include where it’s situated.
Body sensations
Parietal lobe
Brocca’s area?
Include where it’s situated.
Speech production
Frontal lobe, just above the temporal lobe.
Wernicke’s area?
Include where it’s situated.
Understanding speech.
Temporal lobe, just below the parietal lobe.
What is the role of the somatic NS?
Allows you to sense and respond to the environment that you’re in.
What is the role of the autonomic NS?
Regulates the body’s internal environment.
Controls the glands, involuntary muscles from major organs and the blood vessels.
What is the role of the sympathetic NS?
Has an activation function and can affect several organs at once.
Activates when there’s stress and helps you to deal with the stressor.
What is the role of the parasympathetic NS?
Involved in slowing down bodily processes and maintaining calm in a stressful situation.
