Lecture 2 & 3 Questions PDF

Lecture 2 and 3 Questions 1. What are neurons? - Basic units of the nervous system that is responsible for transmitting signals. 2. What are the main parts of a neuron? - Soma (cell body), dendrites, axon, axon terminals (postsynaptic terminals), myelin sheath, and Nodes of Ranvier. 3. W...

Lecture 2 and 3 Questions 1. What are neurons? - Basic units of the nervous system that is responsible for transmitting signals. 2. What are the main parts of a neuron? - Soma (cell body), dendrites, axon, axon terminals (postsynaptic terminals), myelin sheath, and Nodes of Ranvier. 3. What does the cell body (soma) contain? - The nucleus and organelles for cell metabolism. 4. What is the function of dendrites? - To receive signals from other neurons. 5. What does the axon do? - Transmits signals away from the cell body. 6. What is the purpose of the myelin sheath? - To protect and speed up signal transmission along the axon. 7. Where does neurotransmitter release occur in a neuron? - At the axon terminals (postsynaptic terminals). 8. What is a multipolar neuron? - A neuron with multiple dendrites and one axon; common in the CNS. 9. Where are bipolar neurons typically found? - In sensory organs.  Lecture 2 and 3 Questions 10. What role do interneurons play? - They connect other neurons within the CNS. 11. What do oligodendrocytes do? - They form the myelin sheath in the CNS. 12. What is the main function of astrocytes? - To provide support, regulate neurotransmitters, and maintain ion balance. 13. What role do microglia play? - They act as immune cells, clearing debris in the brain. 14. What is depolarization? - The phase where Na+ ions enter the neuron, making the inside more positive. 15. What happens during repolarization? - K+ ions flow out, restoring the negative charge inside the neuron. 16. What is the resting membrane potential? - The stable, negative charge inside a neuron, typically -70 mV. 17. What is the refractory period? - A period following an action potential when the neuron cannot fire again. 18. Why are action potentials "all-or-nothing" events? - Once the threshold is reached, the neuron fires fully; if not, it doesn’t fire at all. 19. What is the threshold for an action potential?  Lecture 2 and 3 Questions - The minimum stimulation level required to trigger an action potential. 20. How does an action potential propagate along an axon? - By moving in a wave-like manner, sometimes jumping between Nodes of Ranvier in myelinated. 21. What is synaptic transmission? - The process of signal transfer from one neuron to another at the synapse. 22. What are excitatory and inhibitory signals? - Excitatory signals bring the next neuron closer to firing; inhibitory signals reduce the likelihood of firing. 23. What is synaptic plasticity? - The ability of synapses to strengthen or weaken over time based on activity, critical for learning and memory. 24. Why are the Nodes of Ranvier important? - They allow faster signal transmission by enabling the action potential to jump between nodes. 25. What is the role of Na+ ions in action potentials? - They are crucial for depolarization during an action potential. 26. What is the role of K+ ions in action potentials? - They are essential for repolarization, restoring the neuron's resting state. 27. What is the ligand-gated ion channels? - Channels that open in response to the binding of specific molecules like neurotransmitters. 28. What is the function of ion pumps in neurons?  Lecture 2 and 3 Questions - To use ATP to transport ions against their concentration gradients, maintaining the resting membrane potential. 29. What are leakage channels? - Channels that are always open, allowing ions to passively move across the cell membrane. 30. What does "saltatory conduction" refer to? - The process where action potentials jump from node to node along a myelinated axon. 31. What are the three components of the cytoskeleton in neurons, and what is their role? - Microtubules, neurofilaments, and microfilaments; they provide structural support and maintain the shape of the neuron. 32. Can you describe the process of an action potential? - An action potential starts with depolarization, where Na+ ions flow into the neuron, making the inside more positive. This is followed by repolarization, as K+ ions exit the neuron, restoring the negative charge inside. Afterward, there is a refractory period, during which the neuron temporarily cannot fire again, ensuring the action potential moves in one direction down the axon until it reaches the axon terminal.  Lecture 2 and 3 Questions 33. Label the neuron: