Topic 1: Neuroglia (Bridge) Flashcards
The Nervous System is divided into which 2 systems?
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
What does the CNS consist of ?
Brain and spinal cord (no nerves)
What does the PNS consist of?
Everything outside the CNS, ex. nerves
carries afferent info to CNS &
Efferent info from CNS to effectors (muscles and glands)
What are the divisions of the PNS?
Somatic Nervous System (SNS) - controls skeletal mm.
Autonomic Nervous System (ANS) - controls heart, smooth mm. in viscera, blood vessels and glands
What does the ANS consist of?
Parasympathetic NS: “rest and digest” & Vagus Nerve CNX carries most of the parasympathetic output
Sympathetic NS: “Fight or Flight”
Enteric Nervous System (ENS): Controls GI tract
What is another term for neurons?
nerve cell bodies
What is another term for nerve fibre
Axon
A bundle of axons in the CNS is
a tract
What is the purpose of Glia?
Glia means glue and Protects and supports neurons (nerve cells)
What type of cells are Schwann cells?
Myelin producing cells in the PNS
What is the node of Ranvier?
the small gap in between the axon
What is the main purpose of a myelin sheath?
- To increase the speed at which impulse propagates along an axon
- It also prevents nerve signal leakage into the surrounding interstitial fluid
______ are myelin producing cells in the CNS
Oligodendrocytes
T/F: Schwann cells are more fragile than oligodendrocytes
False.
Oligodendrocytes are more fragile than Schwann cells
Which CNS disease attacks oligodendrocytes
Multiple Sclerosis
Which cells are star-shaped
Astrocytes
T/F: Astrocytes are the most numerous of the CNS glial cells
True
What is the purpose of Astrocytes
they provide physical support to the fragile neurons, forming a matrix that keeps neurons in place
_______ have long, highly branched processes which end of the walls of capillaries that contribute to the BBB, altering the permeability of brain capillaries
Astrocytes
What severely limits the passage of many harmful substances from blood to the neurons
The Blood brain barrier (BBB)
Which substance in excess causes cells to become overexcited and die
What is this process called?
Glutamate. This process is called excitotoxicity
T/F: The BBB does not hinder the delivery of many potentially important therapeutic agents to the brain
False
_____ is permeable to alcohol, amphetamines and some toxic metals
The BBB.
Trauma, radiation, HT and infection can affect BBB efficiency
What does the Tripartite Synapse consist of ?
Presynaptic neuron
Postsynaptic neuron
Astrocyte
What does the tripartite synapse contribute to?
Neural plasticity
What is neuroplasticity ?
Structural changes in the brain in response to new situations - behaviour, the environment, thinking emotions as well as changes from bodily injury
Chronic pain is an unfortunate product of _______
Neural plasticity
T/F: Pain process is a complex system that can be up-and down-regulated by a number of different factors
True
T/F: Satellite glial cells cover the surfaces of ganglia
True
What are ganglia?
Collection of nerve cell bodies in the PNS
What are nerve cell bodies in the CNS called?
Nuclei
T/F: Satellite glial cells are known to have a similar role to astrocytes in the CNS
True
What are the resident macrophage immune cells of the CNS?
Microglia
What are the cardinal signs of peripheral inflammation ?
Pain, heat, redness, swelling and loss of function
What is neuroinflammation?
may resemble peripheral inflammation in situations such as meningitis, head trauma, autoimmune diseases of the CNS.
Can be used to identify a different event driven by microglia cells,
Group of plant substances found in a variety of fruits and vegetables
Flavonoid
Name the 3 connective tissue layers that protect the CNS from rubbing against bones of the skulls and spine
Dura mater
Arachnoid membrane
Pia mater
Which is the tough fibrous outer layer?
Dura
Which mater has two layers?
Dura. The outer layer anchors the dura to the skull
Which layer is the delicate fibrous spider web-like network of collagen fibers?
Arachnoid membrane
The arachnoid layer extends from the ______ to the _______
Dura mater to pia mater
Which is the inner, delicate, vascularized membrane of the meninges that firmly adhere to the brain
Pia mater
Which cells line the ventricles of the brain and the central canal of the spinal cord
Ependymal cells
What is the CSF?
Cerebrospinal fluid.
Acts to less the impact of a blow to the head
Serves to transport hormones to other areas of the brain
Which sinuses carry reabsorbed CSF back to the blood via the internal jugular veins of the neck?
Dural sinuses aka cranial sinuses
____ are found between the two layers of dura mater
Dural sinuses
What is hydrocephalus
CSF builds up within the ventricles
Hematoma can occur in which spaces of the skull
Subdural and epidural
What is a hematoma?
A localized mass of extravasated blood, usually clotted
What are the symptoms of a cerebral hematoma?
Severe headache, deterioration of consciousness and motor dysfxn
which artery is very susceptible to injury?
Middle meningeal
Which type of hematoma is more common in elderly?
Subdural hematoma
because of brain shrinkage that occurs with aging. The shrinkage stretches and weakens the bridging veins. and are more likely to break in the elderly, even after a minor head injury
What is chronic subdural hamtoma?
An ‘old’ collection of blood and blood breakdown products b/w the surface of the brain and the dura. Blood leaks from the veins slowly over time
Name the Neuroglia in the CNS
Ependymal cells
Oligodendrocytes
Astrocytes
Microglia
Name the Neuroglia in the PNS
Schwann cells
Satellite cells
