Chapter 3 Vocab Flashcards
cell body (soma)
Core region of the cell containing the nucleus and other organelles for making proteins
dendrite
Branching extension of a neuron’s cell membrane that greatly increases the surface area of the cell and collects information from other cells.
axon
“Root,” or single fiber, of a neuron that carries messages to other neurons
dendritic spine
Protrusion from a dendrite that greatly increases the dendrite’s surface area and is the usual point of dendritic contact with the axons of other cells.
axon hillock
Juncture of soma and axon where the action potential begins,
axon collateral
Brach of an axon.
terminal button (end foot)
Knob at the tip of an axon that conveys information to other neurons.
synapse
Junction between one neuron and another that forms the information-transfer site between neurons
sensory neuron
Neuron that carries incoming information from sensory receptors into the spinal cord and brain.
interneuron
Association neuron interposed between a sensory neuron and a motor neuron; thus, in mammals. interneurons constitute most of the neurons of the brain.
motor neuron
Neuron that carries information from the brain and spinal cord to make muscles contract.
bipolar neuron
Sensory neuron with one axon and one dendrite.
pyramidal cell
Distinctive interneuron found in the cerebral cortex.
Purkinje cell
Distinctive interneuron found in the cerebellum
tumor
Mass of the new tissue that grows uncontrolled and independent of surrounding structures.
glial cell
Nervous-system cell that provides insulation, nutrients, and support and that aids in repairing neurons and eliminating waste products.
ependymal cell
Glial cell that makes and secretes cerebrospinal fluid; found on the walls of the ventricles in the brain. “Ependymal cells have one cilia (a hair-like structure) and they all beat in synchrony to circulate cerebrospinal fluid throughout the ventricles.”
astrocyte
Star-shaped glial cell that provides structural support to neurons in the central nervous system and transports substances between neurons and blood vessels. The stuff in the skull is about half neurons, about 48% astrocytes, and 2% other types of cells”
blood-brain barrier
Tight junctions between the cells that compose blood vessels in the brain, providing a barrier to the entry of an array of substances, including toxins, into the brain.
microglia
Glial cells that originate in the blood, aid in cell repair, and scavenge debris in the nervous system “The brain’s immune system”
myelin
Glial coating that surrounds axons in the central and peripheral nervous systems; prevents adjacent neurons from short-circuiting.
oligodendroglia
Glial cells in the central nervous system that myelinate axons.
Schwann cell
Glial cell in the peripheral nervous system that myelinates sensory and motor axons.
multiple sclerosis (MS)
Nervous-system disorder that results from the loss of myelin (glial-cell covering) around neurons.
paralysis
Loss of sensation and movement due to nervous-system injury.
Phospholipid formations
Information flow in neurons
What is the “central dogma” of molecular biology?
DNA -> RNA -> Protein
Basic Neuron Anatomy
Impermeable membrane
Semi-permeable membrane
Astrocyte supporting the synapse
Information flow in neurons
dendrites receive, soma/hillock integrate, axon hillock initiates action potential, axon transmits
Neural computation is a balance of ______ and ______
excitation and inhibition
