Week 4 Flashcards
Who was the first scientist to use a remote neural implant?
Jogo Delgado.
What are the two main classes of cells in the nervous system?
Neurons and glial cells.
What do glial cells provide?
Structural support and assistance in electrical activity.
Name the three types of glial cells.
Astrocytes, microglial cells, and oligodendrocytes.
What is the primary function of astrocytes?
To create the blood-brain barrier and transport ions across the vascular wall.
What is the role of oligodendrocytes?
To produce myelin in the CNS.
What do Schwann cells do?
Produce myelin in the PNS.
What is myelin’s function?
It acts as an electrical insulator to speed up signal transmission.
What is the function of microglial cells?
To act as phagocytes that devour damaged cells.
What is the significance of the blood-brain barrier?
It protects the brain from foreign substances that could harm neural activity.
What are the two components unique to neurons?
Dendrites and axons.
What is the function of dendrites?
To receive information from other neurons.
What are axons?
Long thin structures that carry electrical signals to the axon terminals.
What are nodes of Ranvier?
Gaps in the myelin sheath that facilitate rapid signal transmission.
What is neuronal signaling?
The process of receiving, evaluating, and transmitting information within neurons.
What is the resting membrane potential of a neuron?
Approximately -70 mV.
What maintains the membrane potential?
Ion channels and ion pumps.
How many Na ions are pumped out for every K ion pumped in?
3 Na out, 2 K in.
What happens during depolarization?
Voltage-gated Na channels open, allowing Na to enter the neuron.
What is the Hodgkin–Huxley cycle?
A feedback loop of depolarization caused by opening Na channels.
What is synaptic transmission?
The process of communication between neurons.
Name the two types of synapses.
Chemical synapses and electrical synapses.
What are neurotransmitters?
Chemical messengers released at synapses.
How do neurotransmitters move across the synapse?
They are released into the synaptic cleft and bind to receptors on the postsynaptic membrane.
What triggers neurotransmitter release?
The influx of calcium ions (Ca²⁺) into the axon terminal.
Name the primary excitatory neurotransmitter in the brain.
Glutamate.
Name the primary inhibitory neurotransmitter in the brain.
GABA.
What are two types of acetylcholine receptors?
Nicotinic and muscarinic receptors.
What neurotransmitter is associated with reward and motivation?
Dopamine.
What neurotransmitter regulates mood, sleep, and appetite?
Serotonin.
What structures enable electrical transmission between neurons?
Gap junctions.
What is the main advantage of electrical synapses?
Rapid signal conduction.
What is the main limitation of electrical synapses?
They lack plasticity and cannot amplify signals.
What are microcircuits?
Localized networks of interconnected neurons that process specific information.
What is a corticocortical connection?
A connection between two cortical regions
What are the two subdivisions of the autonomic nervous system?
Sympathetic and parasympathetic systems
What neurotransmitter does the sympathetic system primarily use?
Norepinephrine.
What neurotransmitter does the parasympathetic system primarily use?
Acetylcholine.
What are the three protective membranes of the CNS?
Dura mater, arachnoid mater, and pia mater.
What is cerebrospinal fluid (CSF)?
A fluid that cushions the brain and spinal cord.
What are the ventricles in the brain?
Interconnected cavities filled with CSF.
Name one function of CSF.
Reducing shock during rapid movements.
What can excessive glutamate lead to?
Cell death, stroke, epilepsy, and neurodegenerative diseases.
What diseases are associated with dopamine deficits?
Parkinson’s disease, Alzheimer’s disease, and schizophrenia.
What happens if GABA levels are too high?
It can lead to coma.
What toxin inhibits acetylcholine release?
Botulinum toxin.
What neurotransmitter is involved in the fight-or-flight response?
Norepinephrine.
What is saltatory conduction?
The jumping of action potentials between nodes of Ranvier.
What is hyperpolarization?
A state where the membrane potential becomes more negative than the resting potential.
What is the absolute refractory period?
A period during which Na channels cannot reopen, preventing new action potentials.
