Cells and Structures of the CNS Flashcards
What is the Nervous System divided into?
Central and peripheral nervous system
What are the components of the CNS and its function?
CNS= main centers for correlation and integration of information
- brain
- spinal cord
- meninges and cerebrospinal fluid
- protected by skull and vertebral column bones
What is the PNS and function?
peripheral nervous system - conduct information
to and from the central nervous system
- cranial
- spinal nerves and their associated ganglia.
- bundles of nerve fibers surrounde
What is Autonomic Nervous system?
- distributed throughout the central and
peripheral nervous systems - innervation of involuntary structures, such as
the heart, smooth muscle, and glands
What are the 2 divisions of the autonomic nervous system?
Sympathetic (prepare emergency) and parasympathetic (conserve and restore energy)
What are gray and white matter?
The brain has an inner core of white matter, which is surrounded by an outer covering of gray
matter - the reverse is true in the spinal cored (white matter surrounds a core of grey matter)
- Some important masses of gray matter are however situated deeply within the white matter (ex.:
cerebellar nuclei, thalamic, caudate, and lentiform nuclei).
What does the grey matter consist of?
neuronal
cell bodies and supporting cells (glia,
vasculature)
What is white matter consisting of?
myelinated axons and supporting cells (glia)
Major divisions of the CNS include
- Hindbrain
–Medulla oblongata
–Pons
–Cerebellum - Midbrain
- Forebrain
–Diencephalon
–Cerebrum
What is the cerebral cortex?
covers entire surface of the brain overlying the deep nuclei.
The cortex with deep gray matter comprise the forebrain
cortex is highly folded- this produces gyri (ridges) and sulci (furrows)
major sulci, large sulci, gyri named
major sulci- central sulcus
large sulci- fissures
gyri- named based on their function and/or location
how is the cerebral cortex classified?
divided into major lobes with important sulci delineating the boundaries between lobes
- frontal lobe
- occipital lobe
- parietal lobe
- temporal lobe
- limbic lobe (additional)- consists of cingulate gyrus and parahippocampal gyrus
What is the ventricular system
consists of spaces within the brain that are filled with cerebrospinal fluid CSF
ventricles act as important landmarks, help to grasp spatial relationships within the brain
what produces CSF
ependymal cells of choroid plexus, which lines the ventricles
What are the principle cell types of the CNS?
Nerve cells or neurons (85 billion)
* highly specialized to transmit and integrate electrical impulses
* receive and process information from the external and internal
environment
* may have specific sensory receptors and sensory organs to this function
one nucleus and two
different types of processes:
* axon
* dendrites
Supporting cells
What is an axon?
terminates at a neuronal junction called a synapse at
which electrical impulses are transferred from one cell to the next by
secretion of neuromodulators and neurotransmitters
What do dendrites do?
dendrites receive impulses and carry them toward the cell body
What are the types of neurons/classification
Unipolar, Bipolar, Multipolar, Golgi type 1 axon, Golgi Type 2
Unipolar is a
single neurite divides a short distance from cell body in posterior root ganglia
Bipolar is a
single neurite emerges from either end of cell body in retina, sensory cochlea, vestibular ganglia
Multipolar is a
many dendrites and one long axon, In fiber tracts of brain and spinal cord, peripheral nerves, motor cells of spinal cord
What is golgi type 1?
single long axon
in fiber tracts of brain and spinal cord, peripheral nerves and motor cells of spinal cord
What is golgi type 2?
short axon that with dendrites resembles a star; in cerebral and cerebellar cortex
What are the Cortical and sub-cortical neuronal types?
Spiny neurons, medium spiny neurons, aspiny neurons
