Science
Reflex action
प्रतिवर्ती क्रिया
In Class 10 Science, the topic Reflex Action explains how the body responds rapidly and automatically to a stimulus, often before the brain can process it fully. Students learn the pathway of a reflex arc: receptors detect a change, sensory neurons carry the impulse to the spinal cord, relay neurons connect it to motor neurons, and effectors such as muscles produce the response. Examples like quickly withdrawing a hand from a hot object show how this protective mechanism works, while the brain later receives information about the action.
Practice questions
In reflex action the hand moves away first and full pain is felt later. What is the best reason?MediumLevel 16Which pair is most correct for understanding the difference between voluntary action and reflex action?MediumLevel 16What is the correct function of sensory nerve and motor nerve in a reflex arc?MediumLevel 16What role do heat receptors of skin play at the beginning of a reflex action in humans?MediumLevel 16Why can development of a reflex arc be considered useful for organisms?MediumLevel 16If the sensory nerve in a reflex arc is normal but the intermediate nerve pathway is blocked, what is the most likely result?HardLevel 17A patient can think and speak, but automatic breathing is seriously affected. Which part is most suspicious?HardLevel 17Why does the brain receive information even when its direct role in a reflex action is small?MediumLevel 17Which sequence best represents the scientific understanding of a reflex arc?MediumLevel 17Which statement gives the deepest difference between reflex action and voluntary action?HardLevel 17Which sequence of message flow in a reflex arc is correct?HardLevel 18In which situation is the role of a motor nerve shown most directly?MediumLevel 18Which option correctly differentiates voluntary action and reflex action?MediumLevel 18Which example shows the correct relation between control centre and effector?HardLevel 18Why are walking and withdrawing hand from a hot object different types of actions?MediumLevel 16What do heat receptors in the skin do first at the beginning of a reflex response?MediumLevel 16Why can a reflex arc provide a survival advantage to an organism?MediumLevel 16Why can reflex action be affected if a part of the spinal cord is injured?HardLevel 17Why is a reflex action faster than a voluntary action?MediumLevel 17If a student says that the brain never receives information in a reflex action, what is the correct correction?MediumLevel 17