Answer: Cl- influx or K+ efflux causing hyperpolarization.
- A Na+ influx causing rapid membrane depolarization
- B Cl- influx or K+ efflux causing hyperpolarization
- C Mainly acetylcholine release at the synaptic cleft
- D Neurotransmitter uptake occurring back from the synapse
Correct answer: B. Cl- influx or K+ efflux causing hyperpolarization
Explanation: IPSPs: inhibitory neurotransmitters (GABA, glycine) cause Cl- influx or K+ efflux, hyperpolarizing the membrane, making firing less likely.
Structure of a neuron. Image: LadyofHats (Mariana Ruiz), Public Domain, via Wikimedia Commons.
Concept context
Brain, spinal cord, neurons, reflex arcs, and sense organs.