Assertion: The knee-jerk reflex is an example of a monosynaptic reflex.
Reason: In the knee-jerk reflex, the sensory neuron directly synapses with the motor neuron in the spinal cord without the involvement of an interneuron.
Both Assertion and Reason are true, and the Reason is the correct explanation of the Assertion.
Both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.
Assertion is true, but the Reason is false.
Assertion is false, but the Reason is true.
A tap on the patellar tendon causes the quadriceps muscle to contract in a basic reflex known as the knee-jerk reaction. The muscular spindle in the quadriceps muscle serves as the reflex' sensory receptor by detecting variations in muscle length. A touch on the patellar tendon causes the muscle spindle to stretch, which causes a sensory neuron to send a message to the spinal cord. Without the assistance of an interneuron, a monosynaptic reflex occurs when a sensory neuron in the spinal cord synapses directly with a motor neuron. In the knee-jerk response, the quadriceps muscle contracts as a result of a direct connections between the sensory and motor neurons. Therefore, the assertion is true, and the reason is a correct explanation for it.
Option a is the correct answer.