Which characteristic is not a factor in the speed of the knee-jerk reflex?
A) Myelination
B) Fast synapses
C) IPSPs
D) Axon diameter

Question

Quizplus · Accepted Answer

IPSPs (inhibitory postsynaptic potentials) are inhibitory signals that decrease the likelihood of an action potential firing. The knee-jerk reflex is a simple monosynaptic reflex that only involves one synapse between the sensory neuron and the motor neuron, and does not involve inhibitory signals. Therefore, the presence or absence of IPSPs is not a factor in the speed of the knee-jerk reflex. Myelination, fast synapses, and axon diameter all contribute to faster conduction of the nerve impulse and therefore faster reflexes.

Which Characteristic Is Not a Factor in the Speed of the Knee-Jerk