All flashcards
Flashcard 1: What is the function of the axon in a neuron?
Answer: Transmits electrical impulses away from the cell body. The axon conducts nerve impulses from the soma to the terminal buttons.
Flashcard 2: Which structure insulates axons and speeds up neural impulses?
Answer: Myelin sheath. Fatty white substance that wraps around axons to increase transmission speed.
Flashcard 3: Which ion channels open during the repolarization phase of an action potential?
Answer: Potassium channels. Channels that open to allow potassium efflux during membrane repolarization.
Flashcard 4: Identify the type of neuron that carries information to the central nervous system.
Answer: Sensory neuron. Afferent neurons that relay information from sensory organs to the brain.
Flashcard 5: What is the primary function of neurotransmitter receptors?
Answer: Bind neurotransmitters to initiate a response. Protein structures that receive and respond to specific neurotransmitter molecules.
Flashcard 6: Which part of the neuron contains the synaptic vesicles?
Answer: Axon terminal. The end portion of the axon where synaptic vesicles are located.
Flashcard 7: What is the gap between two neurons called?
Answer: Synapse. The junction between neurons where chemical communication occurs.
Flashcard 8: Identify the type of neuron that carries information to the central nervous system.
Answer: Sensory neuron. Afferent neurons that relay information from sensory organs to the brain.
Flashcard 9: What is the role of motor neurons?
Answer: Transmit signals from the CNS to muscles. Efferent neurons that carry commands from the brain to muscles and glands.
Flashcard 10: Name the type of neuron that connects sensory and motor neurons.
Answer: Interneuron. Neurons within the CNS that process information between sensory and motor neurons.
Flashcard 11: Identify the process of removing neurotransmitters from the synaptic cleft.
Answer: Reuptake. Process where neurotransmitters are recycled back into the presynaptic neuron.
Flashcard 12: What is the significance of the nodes of Ranvier?
Answer: Facilitate rapid conduction of nerve impulses. Gaps in myelin that allow saltatory conduction for faster signal transmission.
Flashcard 13: Which structure contains the neuron's genetic material?
Answer: Nucleus. Control center of the cell that houses DNA and regulates cellular functions.
Flashcard 14: What is the term for the neuron's outer boundary?
Answer: Cell membrane. Selectively permeable barrier that controls ion movement in and out of the neuron.
Flashcard 15: Identify the process by which neurons communicate electrically.
Answer: Action potential. Electrical signal that enables rapid communication between neurons.
Flashcard 16: Name the enzyme that breaks down acetylcholine in the synaptic cleft.
Answer: Acetylcholinesterase. Enzyme that terminates acetylcholine action by breaking it down.
Flashcard 17: What is the role of the synaptic vesicles?
Answer: Store neurotransmitters. Small sacs that contain and release neurotransmitters into the synapse.
Flashcard 18: What effect does an inhibitory neurotransmitter have on the neuron?
Answer: Decreases likelihood of firing an action potential. Makes the postsynaptic neuron less likely to reach threshold and fire.
Flashcard 19: What effect does an excitatory neurotransmitter have on the neuron?
Answer: Increases likelihood of firing an action potential. Makes the postsynaptic neuron more likely to reach threshold and fire.
Flashcard 20: Which ion channels open during the repolarization phase of an action potential?
Answer: Potassium channels. Channels that open to allow potassium efflux during membrane repolarization.
Flashcard 21: Which ion channels open during the depolarization phase of an action potential?
Answer: Sodium channels. Voltage-gated channels that allow sodium influx during action potential initiation.
Flashcard 22: What is the basic structural unit of the nervous system?
Answer: Neuron. The fundamental building block that processes and transmits information throughout the nervous system.
Flashcard 23: Identify the part of the neuron that receives signals from other neurons.
Answer: Dendrites. Branch-like extensions that receive incoming chemical signals from other neurons.
Flashcard 24: What is the gap between two neurons called?
Answer: Synapse. The junction between neurons where chemical communication occurs.
Flashcard 25: Name the chemical messengers that cross synapses.
Answer: Neurotransmitters. Chemical substances that carry signals between neurons across synaptic gaps.
Flashcard 26: What is the resting potential of a neuron typically measured in millivolts?
Answer: -70 mV. The electrical charge of an unstimulated neuron at rest.
Flashcard 27: Identify the term for a brief electrical charge that travels down an axon.
Answer: Action potential. A rapid electrical signal that propagates along the axon membrane.
Flashcard 28: What process describes a neuron returning to its resting state?
Answer: Repolarization. The process of restoring the neuron's negative electrical charge after firing.
Flashcard 29: Which ion enters the neuron during depolarization?
Answer: Sodium (Na⁺). Positive ion that rushes into the neuron causing depolarization.
Flashcard 30: What ion exits the neuron during repolarization?
Answer: Potassium (K⁺). Positive ion that flows out of the neuron to restore resting potential.