Nervous System Overview, Nervous Tissue, Nerve Protection & Support, Nerve Impulses, Protecting the Brain Flashcards
Neurons are stimulated by what?
- environment
- other neurons
auto-
self
Intergration
Processing and interpreting the information
Parasympathetic Division
- reduces sympathetic response
- rest & digest
Axons
Send impulses away from the cell body
polar-
end
Sympathetic Division
- used in emergency situations
- fight or flight
audi-
oto-
Hearing
opt-
Vision
Ependymal cells
Secrete and circulate cerebrospinal fluid
Afferent neurons
Carry impulses towards the CNS
PNS
Peripheral Nervous System
-ellum
Smaller
mening-
Membrane
astro-
Star
CNS
Central Nervous System
How is myelin formed?
The Schwann cell wraps itself around the axon
Choroid plexuses
Clusters of capillaries in ventricles that secrete CSF
dendr-
Treelike
As a whole, the myelin wrappings are called the what?
Myelin sheath
What is between the arachnoid layer and the pia mater?
Cerebrospinal fluid (CSF)
Response
Activation of muscles or glands
Thin layer containing lots of blood vessels
Pia mater
A waxy insulation wrapped around axons
Myelin
Depolarization
Sodium rushes into the neuron and reverses the charges
Astrocytes
Support and anchor neurons to surrounding capillaries
How many systems is the nervous system divided into?
2
Autonomic System
(2 divisions)
Involuntary muscle control (sympathetic, parasympathetic)
What do neurotransmitters cause to open in the next neuron
Channels
Synapse
Where two neurons meet
Satellite cells
Support and anchor neurons in the CNS
gli
Glue
Cell body contains (3)
- nucleus
- cytoplasm
- organelles
Efferent neurons
Carry impulses away from the CNS
Thin, cobweb-like layer
Arachnoid membrane
As the impulse passes, what diffuses out of the neuron?
Potassium (re-polarization, resets charges)
neuro-
Nerve
Schwann cells
Provide myelin to neurons in the PNS
oligo-
Few
Interneurons
Connect afferent and efferent neurons
What are processes divided into?
- dendrites
- axons
Synaptic cleft
The space between two neurons
Dendrites
Bring impulses towards the cell body
How does CSF protect the brain?
- prevents it from contacting the skull
- maintains the blood-brain barrier, which controls brain homeostasis and prevents infection
photo-
Light
Sensory Division
Sends impulses from senses to CNS
Somatic system
Voluntary muscle control
A resting neuron has a what?
Resting potential
Thick, tough layer
Dura mater
Meninges
Three layers of protective connective tissue protecting the brain and spinal cord
Where is CSF produced?
Ventricles
Sensory input
It detects changes (stimuli) inside and outside of the body
Microglia
Provide immune response to CNS
Axon terminals are at the end of nerve cells and release what?
Neurotransmitters
Motor division
Sends impulses from CNS to muscles and glands (autonomic, somatic)
Interventricular formamen (formen of Monro)
Connects lateral ventricles to the third ventricle
Oligodendrocytes
Provide myelin insulations to neurons in the CNS
What are in-between Schwann cells?
Nodes of Ranvier
Myelin helps what travel more quickly?
Nerve impulses
What are the four ventricles?
- laterals (right and left)
- third
- fourth
Neurons
- conduct impulses around the body
- 10% of all nerve cells
cereb-
enceph-
Brain
What makes up the central nervous system (CNS)?
The brain and spinal cord
Arachnoid granulations
Absorbs CSF into the bloodstream
A depolarization is known as the what?
Action potential
CSF is constantly being
- produced
- circulated
- reabsorbed
Neuroglia
- “nerve-glue”
- supports, insulates and protects neurons
- 90% of all nerve cells
Neurilemma
The outer layers of the Schwann cell
The movement of ions causes a what?
Nerve impulse
What releases neurotransmitters across the synaptic cleft?
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