This division of the nervous system contains the brain and spinal cord.
CNS
At rest, which ion is found in a higher concentration inside the neuron
K+ (potassium)
These branching structures of a neuron primarily receive information and carry it toward the cell body.
Dendrites
This root of a spinal nerve carries sensory information into the spinal cord.
Dorsal root
The movement of particles from an area of higher concentration to lower concentration is called this.
Diffusion
A collection of neuron cell bodies in the CNS is called this.
nucleus
When threshold is reached, these channels rapidly open, allowing Na⁺ to rush into the neuron.
sodium voltage gated channels
This part of a neuron carries an electrical signal away from the cell body toward its terminals.
Axon
This root carries motor information out of the spinal cord
ventral root
The movement of water across a selectively permeable membrane is called this.
Osmosis
A collection of neuron cell bodies in the PNS is called this.
ganglion
The movement of Na⁺ into the neuron causes the membrane potential to become more positive. This phase of the action potential is called what?
depolarization
These glial cells form the myelin sheath in the PNS, while oligodendrocytes perform this job in the CNS.
Schwann cells
This structure along the dorsal root contains the cell bodies of sensory neurons.
DRG (dorsal root ganglion)
A cell is placed in a solution with the same solute concentration as the inside of the cell. The cell remains approximately the same size.
Isotonic solution
This type of nervous tissue is made mostly of myelinated axons and gets its lighter appearance from myelin.
white matter
During this phase, voltage-gated K⁺ channels are open and K⁺ moves out of the neuron, making the inside more negative again.
repolarization
These PNS glial cells surround and support neuron cell bodies within ganglia.
Satellite cells
These long spinal nerve roots travel inferiorly below the end of the spinal cord and resemble a horse's tail.
cauda equina
A cell is placed in a solution and begins to swell because water moves into it. What type of solution is the cell in?
hypOtonic
What are bundles of axons called in the CNS, and what are they called in the PNS?
Tracts in the CNS
nerves in the PNS
Put these events in the correct order:
K⁺ exits → resting membrane potential → Na⁺ enters → threshold is reached
Resting membrane potential → threshold is reached → Na⁺ enters/depolarization → K⁺ exits/repolarization?
These are the six major glial cells. Name all six and identify whether each is found in the CNS or PNS.
astrocytes, oligodendrocytes, microglia, and ependymal cells (CNS)
Schwann cells and satellite cells (PNS)
A sensory signal enters the spinal cord through the dorsal root. A motor signal then leaves the spinal cord through which root, and what type of signal is it: afferent or efferent?
ventral root and efferent
A cell is placed in a solution with a higher solute concentration outside the cell. What type of solution is this, which direction does water move, and what happens to the cell?
hypertonic solution
water moves out of the cell and the cell shrinks