At the Frog NMJ, Why Does Lowering the Extracellular Calcium

question 41

Multiple Choice

At the frog NMJ, why does lowering the extracellular calcium and adding extracellular magnesium reduce the amplitude of EPPs?

• A) This results in a reduced probability of quantal release of transmitter due to reduced calcium influx.
• B) This results in an increased probability of quantal release of transmitter due to increased magnesium influx.
• C) This results in a reduced probability of quantal release of transmitter due to a reduced depolarization of the nerve terminal membrane.
• D) This results in a reduced probability of quantal release of transmitter due to a increased depolarization of the nerve terminal membrane.
• E) This results in a change in the nerve terminal input resistance which changes the magnitude of the EPP without a change in the probability of quantal release of transmitter.

---

Definitions:

Axon

An elongated, thin extension of a neuron, or nerve cell, that generally transports electrical signals from the cell body of the neuron.

Messages

Units of communication that convey information, thoughts, or ideas from one entity to another.

Central Nervous System

The part of the nervous system consisting of the brain and spinal cord.

Brain

The complex organ located in the skull that is responsible for cognitive function, processing information, and controlling most of the activities of the body.