Final answer:
Gamma motor neurons do indeed make muscle spindles more sensitive to stretch by adjusting the tension in intrafusal fibers within the spindles.
Step-by-step explanation:
The statement that gamma motor neurons make muscle spindles more sensitive to stretch is true. Gamma motor neurons are responsible for maintaining the sensitivity of muscle spindles, which are sensory receptors within the muscle that detect changes in muscle length. These neurons do this by adjusting the tension in the specialized muscle fibers called intrafusal fibers within the spindles. When the gamma motor neurons are activated, they cause the intrafusal fibers to contract, which keeps the spindle taut and responsive to stretch, even when the muscle itself is shortened. This mechanism ensures that the muscle spindles can provide accurate sensory feedback to the central nervous system about muscle length and the speed of length changes, which is critical for coordination and movement control.