Biology · PYQ NEET UG 2019(2)

Which of the following statements is NOT correct?

1. In the knee-jerk reflex, stimulus is the stretching of muscle and response is its contraction.
2. An action potential in an axon does not move backward because the segment behind is in a refractory phase.
3. Depolarisation of hair cells of cochlea results in the opening of the mechanically gated potassium-ion channels.
4. Rods are very sensitive and contribute to daylight vision.