Lecture 1 Structure and Functions of Cells of the Nervous System Flashcards
Saltatory Conduction
- Conduction of action potentials by myelinated axons - The action potential appears to jump from one node of Ranvier to the next
Postsynaptic potentials
- Alterations in the membrane potential of a postsynaptic neuron, produced by the liberation of a neurotransmitter at the synapse
Binding Site
- The location on a receptor protein to which a ligand binds
Ligand (AKA Neurotransmitter)
- A chemical that binds with the binding site of a receptor
Dendritic Spine
- A small bud on the surface of a dendrite, with which a terminal button of another neuron forms a synapse
Presynaptic Membrane
- The membrane of a terminal button that lies adjacent to the postsynaptic membrane and through which the neurotransmitter is released
Postsynaptic membrane
- The membrane located on the dendrite of the neuron that receives the information
Synaptic Cleft
- The space between the presynaptic membrane and the postsynaptic membrane that is about 20nm wide
Synaptic Vesicle
- A small, hollow, beadlike structure found in the terminal buttons - Contains molecules of a neurotransmitter
Release Zone
- A region of the interior of the presynaptic membrane of a synapse to which synaptic vesicles attach and release their neurotransmitter into the synaptic cleft
Activation of receptors POSTSYNAPTIC RECEPTOR
- A receptor molecule in the postsynaptic membrane of a synapse that contains a binding site for a neurotransmitter
Activation of receptors NEUROTRANSMITTER-DEPENDENT ION CHANNEL
- An Ion channel that opens when a molecule of a neurotransmitter binds with a postsynaptic receptor
Activation of receptors IONOTROPIC RECEPTOR
- A receptor that contains a binding site for a neurotransmitter and an ion channel that opens when a molecule of the neurotransmitter attaches to the binding site
Activation of receptors METABOTROPIC RECEPTOR
- A receptor that contains a binding site for a neurotransmitter - Activates an enzyme that begins a series of events, opening an Ion channel elsewhere in the membrane of the cell when a molecule of the neurotransmitter attaches to the binding site
Postsynaptic Potentials EXCITATORY POSTSYNAPTIC POTENTIAL (EPSP)
- An excitatory depolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button
Postsynaptic Potentials INHIBITORY POSTSYNAPTIC POTENTIAL (IPSP)
- An inhibitory hyper polarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button
Termination of postsynaptic potentials REUPTAKE
- The reentry of a neurotransmitter just liberated by a terminal button back through its membrane, thus terminating the postsynaptic potential
Termination of postsynaptic potentials ENZYMATIC DEACTIVATION
- The destruction of a neurotransmitter by an enzyme after its release, for example, the destruction of acetylcholine by acetylcholinesterase
Termination of postsynaptic potentials ACETYLCHOLINE (Ach)
- A neurotransmitter found in the brain, spinal cord, and parts of the peripheral nervous system - Responsible for muscular contraction - Active in memory, attention, and muscle control
Termination of postsynaptic potentials ACETYLCHOLINESTERASE (AChE)
- The enzyme that destroys acetylcholine soon after it is liberated by the terminal buttons, thus terminating the postsynaptic potential
Effect of Postsynaptic potential
- Neural Integration
Neural Integration
- The process by which inhibitory and excitatory postsynaptic potentials summate and control the rate of firing of a neuron
Autoreceptor
- A receptor molecule located on a neuron that responds to the neurotransmitter released by that neuron
Heteroreceptor
- The receptor on the receiving neuron
Autoreceptors have a variety of functions
- Regulate the internal processes of the cell - Regulate synthesis of the neurotransmitter - Regulate the release of a neurotransmitter - Generally serve to inhibit the activity of a transmitter
Axoaxonic Synapses PRESYNAPTIC INHIBITION
- The action of a presynaptic terminal button in an axoaxonic synapse - Reduces the amount of neurotransmitter released by the postsynaptic terminal button
Axoaxonic Synapses PRESYNAPTIC FACILITATION
- The action of a presynaptic terminal button in an axoaxonic synapse - Increases the amount of neurotransmitter released by the postsynaptic terminal button
Non-synaptic Chemical Communication NEUROMODULATORS
- A naturally secreted substance that acts like a neurotransmitter except that it is nor restricted to the synaptic cleft but diffuses through the extracellular fluid
Non-synaptic Chemical Communication PEPTIDE
- A chain of amino acids joined together by peptide bonds. Most neuromodulators, and some hormones, consist of peptide molecules
Non-synaptic Chemical Communication HORMONE
- A chemical substance that is released by an endocrine gland and that has effects on target cells in other organs
Non-synaptic Chemical Communication ENDOCRINE GLAND
- A gland that liberates its secretions into the extracellular fluid around capillaries and hence into the bloodstream
drug class mantra
- There are classes of drugs and the classes are determined by the mechanism of action
Six primary neurotransmitters
- Gaba - Norepinephrine - glutamate - Dopamine - Seritonin - Acetylcholine
Acetylcholine is broken down by?
- Acetylcholinesterase
Four most common electrolytes
- Sodium + - Potasium + - Chloride - CO2
If it ends in “ase” its most likely a?
- Enzyme
Reversed Prompt
- Comprised of the Brain and Spinal Cord - Encased WITHIN the Skull and Spinal column
Central Nervous System (CNS)
Reversed Prompt
- Comprised of Nerve tissue located OUTSIDE of the brain and Spinal cord
Peripheral Nervous System (PNS)
Reversed Prompt
- Detects changes in the external OR internal environment and sends information about these changes to the CNS
Sensory Neuron
Reversed Prompt
- Located WITHIN the CNS that controls the contraction of a muscle or the secretion of a gland
Motor Neuron
Reversed Prompt
- Located ENTIRELY WITHIN the CNS
Interneuron
Reversed Prompt
- Cell body of a neuron, which contains the nucleus
Neuron Basic Structure SOMA or Cell Body
Reversed Prompt
- A branched treelike structure attached to the soma of a neuron - Receives info from the terminal button of other neurons
Neuron Basic Structure DENDRITE
Reversed Prompt
- The long thin cylindrical structure that conveys info from the soma of a neuron to its terminal button
Neuron Basic Structure AXON
Reversed Prompt
- A junction between the terminal button of an axon and the membrane of another neuron
Neuron Basic Structure SYNAPSE
Reversed Prompt
- A neuron with one axon and many dendrites attached to its soma
Multipolar Neurons
Reversed Prompt
- A Neuron with one axon and one dendrite attached to its soma
Bipolar Neurons
Reversed Prompt
- A neuron with one axon attached to its soma - The axon divides, one branch receiving sensory info and the other sending the info into the CNS
Unipolar Neurons
Reversed Prompt
- The bud at the end of a branch of an axon - Forms synapses with another neuron and sends info to that neuron
Neuron Basic Structure TERMINAL BUTTON
Reversed Prompt
- A chemical that is released by a terminal button - Has an excitatory or inhibitory effect on another neuron
Neuron Basic Structure NEUROTRANSMITTER
Reversed Prompt
- A structure consisting principally of lipid molecules that defines the outer boundaries of a cell and also constitutes many of the cell organelles
Internal Structure MEMBRANE
Reversed Prompt
- The viscous, dimi-liquid substance contained in the interior of a cell
Internal Structure CYTOPLASM