Divisions & Anatomical Terms
This main division of the nervous system consists exclusively of the brain and spinal cord.
What is the Central Nervous System (CNS)?
These glial cells wrap around axons in the Peripheral Nervous System (PNS) to form myelin sheaths.
What are Schwann cells?
Neurons generally do not undergo cell division after development, meaning they have this special characteristic
What is amitotic?
According to Ohm’s Law , as electrical resistance across a membrane increases, current does this.
What is decreases?
The fluid-filled space separating the presynaptic and postsynaptic neurons at a chemical synapse is called this.
What is the Synaptic cleft?
This motor subdivision of the PNS controls involuntary activities, such as heart rate and digestion.
What is the Autonomic Nervous System (ANS)?
These star-shaped CNS glial cells anchor neurons to blood capillaries and help form the blood-brain barrier.
What are Astrocytes?
These branching neuron processes serve as the main receptive or input regions that convey incoming signals toward the cell body.
What are Dendrites?
The typical resting membrane potential of a resting neuron is approximately this voltage.
What is -70 mV?
This chemical neurotransmitter is released at neuromuscular junctions and by all somatic motor neurons that stimulate skeletal muscle.
What is Acetylcholine (ACh)?
A bundle of axon processes located inside the Central Nervous System (CNS) is known as a ________, whereas a bundle in the PNS is a nerve.
What is a Tract?
These CNS neuroglia act as the primary immune defense and phagocytes to clear out pathogens and cellular debris.
What are Microglia?
This structural type of neuron has 3 or more processes (1 axon and multiple dendrites) and is the most common type in the human body.
What is a Multipolar neuron?
These types of membrane channels are continuously open, allowing passive diffusion of ions down their concentration gradients.
What are Leakage (nongated) channels?
An Excitatory Postsynaptic Potential (EPSP) causes local membrane ________, bringing the postsynaptic neuron closer to threshold.
What is Depolarization?
A collection of neuron cell bodies located within the Peripheral Nervous System (PNS) is called a ________.
What is a Ganglion?
These cells line the central cavities of the brain and spinal cord, helping to form a protective barrier and circulate cerebrospinal fluid.
What are Ependymal cells?
These neurons carry impulses away from the CNS to effector organs like muscles and glands.
What are Motor (efferent) neurons?
These gated channels open or close directly in response to a change in the membrane potential voltage.
What are Voltage-gated channels?
This neuropeptide functions as a natural opiate in the body, reducing our perception of pain.
What are Endorphins?
This specific functional division of the Autonomic Nervous System (ANS) is responsible for the "fight-or-flight" response during stress or exercise.
What is the Sympathetic Division?
While Schwann cells form myelin in the PNS, these cells form myelin sheaths around multiple axons within the CNS.
What are Oligodendrocytes?
This rare structural type of neuron has only two processes (one axon and one dendrite) and is found in special sense organs like the retina of the eye.
What is a Bipolar neuron?
During the resting state of a neuron, these specific gated channels are completely closed until threshold is reached.
What are Voltage-gated Na^+ and K^+ channels?
Rapid, automatic responses to stimuli (like spinal reflexes) in which a single stimulus always produces the same predictable response are examples of this type of neural processing.
What is Serial processing?