Neurons and Signaling Flashcards
What is the main function of dendrites in a neuron?
Dendrites receive stimuli.
What do Schwann cells do?
Answer: They insulate the neuron with a myelin sheath.
What is the function of the Nodes of Ranvier?
Answer: They are gaps in the insulation that facilitate the rapid conduction of nerve impulses.
What happens during the resting potential of a neuron?
Answer: The Na/K pumps are ON, and Na+ gates are CLOSED, maintaining a -70 mV negative charge inside the neuron compared to outside.
What occurs during the depolarizing phase of an action potential?
Answer: The Na/K pumps are OFF, and the Na+ gates are OPEN, allowing Na+ to enter the neuron.
What is the refractory period?
Answer: The time during which the neuron cannot respond to a new signal.
What is saltatory conduction?
Answer: The process in myelinated neurons where the signal jumps under the Schwann cells, speeding up signal transmission.
What triggers calcium channels to open at the axon end of a synapse?
Answer: An incoming electrical signal.
What role do pre-synaptic vesicles play in synaptic transmission?
Answer: They release neurotransmitters into the synaptic cleft.
What enzyme breaks down acetylcholine in the synaptic cleft?
Answer: Acetylcholinesterase
What neurotransmitter is responsible for muscle contractions?
Acetylcholine.
Which neurotransmitter is associated with emotions such as depression and aggression?
Answer: Serotonin.
What is the role of dopamine in the brain?
Answer: It affects control of movement, emotions, pleasure, and pain.
