Cells of The Nervous System
The 2 kinds of cells that comprise the nervous system.
What are neurons and glia?
The substance on which vertebrate neurons depend almost entirely.
What is glucose?
The all-or-none law.
What is the name of the law that states that the amplitude and velocity of an action potential are independent of the intensity of the stimulus that initiated it?
Excitatory postsynaptic potential.
What is the graded depolarization that decays over time and space, making it more likely that a neuron will fire?
Helps regulate motor movement, balance, and coordination.
What is the cerebellum?
The cells that help synchronize the activity of the axon by wrapping around the presynaptic terminal and taking up chemicals released by the axon.
What are astrocytes?
__________ neurons are to sending information as __________ neurons are to receiving information.
What are motor and sensory neurons?
The absolute refractory period.
What is the time, after an action potential, when a neuron cannot produce another action potential?
The finding that repeated stimuli can have a cumulative effect and can produce a nerve impulse when a single stimuli is too weak.
What is temporal summation
Associated with motivated emotions including eating.
What is the hypothalamus?
The cells that remove waste material, viruses, and fungi from the brain.
What are microglia?
The inside charge of the neuron.
What is slightly negative?
How the action potential travels down the axon.
What is by jumping from node to node?
Occurs when synaptic input selectively opens the gates for positively charged potassium ions to leave the cell, or negatively charged chloride ions to enter the cells.
What is inhibitory postsynaptic potential?
The thalamus.
What is the sensory relay station?
Radial glia.
What are the cells that guide the migration of neurons and the growth of their axons and dendrites during embryonic development?
During its resting state, __________ are more concentrated outside the neuron while __________ are more concentrated inside the neuron.
What are sodium and potassium ions?
The type of signal that travels down the axon (within the neuron).
What is an electrical signal?
The periodic production of action potentials despite synaptic input.
What is the spontaneous firing rate?
Responsible for memories, especially memories of individual events.
What is the hippocampus?
Why the blood-brain barrier is important.
What is the fact that the cells of the brain generally do not regenerate so harmful materials must be blocked before they enter the brain.
Surrounds the axon and speeds transmission of the signal.
What is the myelin sheath?
The number of neurotransmitters released by most neurons.
What is 2 or more?
The 2 ways in which negative feedback in the brain is accomplished.
What are autoreceptors and postsynaptic neurons?
Contain cerebrospinal fluid, provide cushioning for the brain, and contain hormones and nutrition for the brain.
What are the ventricles?