Ch 4 CNS Yr 12 Flashcards
What organs make up the CNS
spine and brain
What is the PNS?
peripheral nervous system
nerves that connect the sensory receptors and muscles and glands.
What part of the skull is the CRANIUM?
The dome that covers the brain - top and back.
What protects the spinal cord?
the vertebral column
What does the term “Meninges” mean in English?
Membranes
What is the outer layer of the meninges?
What are its features?
Dura Mater
tough and fibrous
Where in the CNS does the dura mater stick to the bone?
skull
What is the middle layer of the meninges?
Why is it called this?
Arachnoid mater
It resembles cobwebs.
What is the inner layer of the meninges?
Pia mater
In which layer of the meninges would you find blood vessels?
Pia mater
What fills the gaps between the layers of the meninges?
Cerebrospinal fluid
In the spinal cord, the meninges are attached to …
fatty layer
What is the CSF
Cerebrospinal fluid
Where would you find CSF?
it circulates through gaps in the brain and the canal in the spinal cord.
What does the CSF look like?
What does it contain?
clear, watery fluid
a few cells, glucose, protein, urea and salts.
What are the 3 functions of the Cerebrospinal fluid?
protection - acts as shock absorber
support - brain “floats “ in liquid
transport - formed in the blood, takes nutrients to and wastes from the brain
What is the Cerebrum?
Largest part of the brain - outer surface of grey matter (cerebral cortex), white matter and the basal ganglia
What is grey matter made of?
neuron cell bodies
dendrites
unmyelinated axons
What is white matter made of?
myelinated axon sheaths
Basal ganglia
grey matter deep in the cerebrum
Why is the cerebral cortex folded?
To increase its surface area. Allows more neurons.
What are the ridges (upper part) of the cerebral cortex called?
convolutions, gyrus/gyri
What are the downfolds ( valleys) of the cerebral cortex called?
fissures , sulcus, sulci
What is the longitudinal fissure?
deep cleft that almost divides the cerebrum into two halves, the cerebral cerebrum.
What are the cerebral hemispheres? What do they control?
two halves of the cerebrum.
Left = logical Right = creative
Name the 4 lobes of the cerebral hemispheres (4 lobes for each hemisphere).
frontal, temporal, occipital, parietal.
What is the 5th lobe, deep in the brain
insula.
What are some mental activities performed by the cerebral cortex.
thinking, reasoning, learning, memory, intelligence and sense of responsibility.
info from senses
control of voluntary muscle.
What are the three areas of the cortex?
sensory
motor
association - intellectual and emotional
How are memories stored?
In links between neurons, not in individual cells.
Are the two hemispheres identical
no in right handed people the size of the lobes differ
Where is the language centre in most people?
Left
Where is the art and music centre controlled?
right hemisphere
What does the word “olfactory” mean?
smell
tract
bundles of nerve fibres inside the CNS.
OUTSIDE = nerves
What are the three types of tracts?
(what do they connect?
connections within the hemisphere
connections between hemispheres
connections from hemisphere to othe parts of brain/ spinal cord.
What do the basal ganglia control?
initiate and suppress movement.
