Select the correct answer from each drop-down menu. When the knee is hit with a rubber hammer, the leg kicks forward, and then returns to the original position. This is an example of a spinal reflex arc. The sensation of the hammer travels to the , where it activates motor neurons that cause the leg to move. This reflex is part of the nervous system.

The sensation of the hammer travels to the Spinal cord where it activates motor neurons that cause the leg to move. This part of nervous system is called vegetative nervous system.

Explanation:

The human reflexes are not planned. When a knee is hit by a hammer the knee tends to move due to the automatic reflex. This is usually called knee jerrk. The doctors hit the knee with a hammer to check the stimulus response in a human. The sensory signals activates the neurons which gives signals to spinal cord where motor neurons are activated causing in an immediate response from the knee.