Chapter 11: Nervous Tissue Flashcards

These flashcards help in reviewing key vocabulary from Chapter 11 on Nervous Tissue in Visual Anatomy and Physiology.

Neurons

Nerve cells specialized for intercellular communication.

Dendrites

Highly branched parts of a neuron that receive stimuli from the environment or other neurons.

Cell body

Part of the neuron that contains the nucleus and organelles.

Axon

Long extension of a neuron that transmits signals to other cells.

Synapse

The junction where a neuron communicates with another cell.

Neuroglia

Supportive cells in the nervous system that protect and support neurons.

Central Nervous System (CNS)

Part of the nervous system that includes the brain and spinal cord.

Peripheral Nervous System (PNS)

All nervous tissue outside the CNS, including sensory and motor pathways.

Resting membrane potential

The electrical potential difference across the membrane of a neuron at rest.

Action potential

A rapid electrical signal that travels along the axon of a neuron.

Graded potential

A temporary change in membrane potential that is localized and can vary in size.

EPSP (Excitatory Postsynaptic Potential)

A graded depolarization event that brings the membrane potential closer to threshold.

IPSP (Inhibitory Postsynaptic Potential)

A graded hyperpolarization event that moves the membrane potential further from threshold.

Wallerian degeneration

The process that occurs after an axon is injured, leading to degeneration of the segment distal to the injury.

Myelin sheath

A protective insulating layer that surrounds axons, formed by oligodendrocytes in the CNS and Schwann cells in the PNS.

Saltatory propagation

The process by which action potentials jump from node to node along myelinated axons.

Chemical synapse

A synapse where neurotransmitters transmit signals from one neuron to another.

Neurotransmitter

Chemicals that transmit signals across a synapse from one neuron to another.

Excitatory neurotransmitters

Neurotransmitters that increase the likelihood of a postsynaptic action potential.

Inhibitory neurotransmitters

Neurotransmitters that decrease the likelihood of a postsynaptic action potential.

Regulatory neurons

Neurons that facilitate or inhibit activities of presynaptic neurons.

Neurotransmitter release\n\n

The process by which neurotransmitters are released from the presynaptic neuron into the synaptic cleft.\n\n

Receptors\n\n

Proteins on the postsynaptic neuron that bind to neurotransmitters and trigger a response.\n\n

Excitatory Postsynaptic Potential (EPSP)\n\n

A change in the postsynaptic membrane potential that makes it more likely to generate an action potential.\n\n

Inhibitory Postsynaptic Potential (IPSP)\n\n

A change in the postsynaptic membrane potential that makes it less likely to generate an action potential.\n\n

Neural plasticity\n\n

The ability of the nervous system to change its structure and function in response to experience or damage.\n\n

Neurogenesis\n\n

The process by which new neurons are formed in the brain.\n\n

Signal transduction\n\n

The process by which a chemical or physical signal is transmitted through a cell as a series of molecular events.

Synaptic pruning\n\n

The process of eliminating unnecessary or unused synapses during development to improve the efficiency of neural connections.

Action potential threshold\n\n

The minimum membrane potential that must be reached for an action potential to occur.\n\n

Refractory period\n\n

The period of time following an action potential during which a neuron is unable to fire another action potential.\n\n

Node of Ranvier\n\n

Gaps in the myelin sheath of axons where action potentials are regenerated.\n\n

Oligodendrocytes\n\n

Glial cells in the CNS that produce myelin sheaths for axons.\n\n

Schwann cells\n\n

Glial cells in the PNS that produce myelin sheaths for axons.\n\n

Axon terminal\n\n

The end part of an axon where neurotransmitters are released into the synapse.\n\n

Synaptic cleft\n\n

The small gap between the presynaptic and postsynaptic neurons where neurotransmitters are released.\n\n

Calcium ions (Ca²+)\n\n

Ions that play a crucial role in neurotransmitter release from presynaptic neurons.\n\n

Long-term potentiation (LTP)\n\n

A long-lasting enhancement in signal transmission between two neurons that results from stimulating them simultaneously.\n\n

Long-term depression (LTD)\n\n

A long-lasting decrease in synaptic strength that occurs when two neurons are not activated together.\n\n

Neurotransmitter recycling\n\n

The process by which neurotransmitters are taken back into the presynaptic neuron after they have been released.\n\n

Excitotoxicity\n\n

A process where excessive stimulation by excitatory neurotransmitters leads to neuron injury or death.\n\n

Functional connectivity\n\n

A measure of the temporal correlation between spatially remote brain regions, often assessed using fMRI.\n\n

Structural plasticity\n\n

The ability of connections between neurons to change in structure as a result of learning or experience.\n\n

G-protein coupled receptors (GPCRs)\n\n

A large family of receptors that detect molecules outside the cell and activate internal signal transduction pathways.\n\n

Antagonist\n\n

A substance that blocks the action of a neurotransmitter at its receptor.\n\n

Agonist\n\n

A substance that mimics the action of a neurotransmitter at its receptor.\n\n

Ionotropic receptors\n\n

Receptors that form an ion channel pore and allow ions to flow directly across the membrane upon activation.\n\n

Metabotropic receptors\n\n

Receptors that are linked to a G-protein and activate a cascade of intracellular events, but do not form an ion channel.\n\n

Corticostriatal pathway\n\n

A neural pathway that connects the cerebral cortex to the striatum, involved in the regulation of voluntary motor control and reward.\n\n

Amygdala\n\n

A region of the brain involved in emotion regulation and the processing of memory and decision-making.\n\n