1. Name the three types of nerves and explain their functions.
2. What is a reflex action? Explain with an example.
3. How are dust particles in the air we breathe filtered in our nose?
4. Mention three ways to take care of our eyes.
Answer (2)
The three types of nerves are sensory, motor, and interneurons, each serving distinct functions in the nervous system. A reflex action is an automatic response to a stimulus, exemplified by pulling your hand away from something hot. Dust particles are filtered by nasal hairs and mucus in the nose, and to care for our eyes, regular check-ups, protective eyewear, and reducing screen time are recommended.
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Types of Nerves and Their Functions :
Sensory Nerves (Afferent Nerves) : These nerves are responsible for carrying signals from sensory receptors (such as those in the skin, eyes, ears, nose, and tongue) to the central nervous system. They help in detecting external stimuli like touch, temperature, and pain, allowing us to perceive the environment.
Motor Nerves (Efferent Nerves) : These nerves carry signals from the central nervous system to the muscles and glands. They are involved in initiating muscle contraction and glandular secretions, enabling movement and various bodily functions.
Mixed Nerves : These nerves contain both sensory and motor fibers, allowing them to carry signals in both directions. A common example of mixed nerves is the spinal nerves, which manage functions like reflexes and voluntary actions.
Reflex Action :
A reflex action is an automatic, rapid response to a stimulus that does not involve conscious thought. It is a protective mechanism that helps minimize damage to the body.
Example : When you accidentally touch a hot stove, sensory nerves in your skin detect the heat. This message immediately travels to the spinal cord, which sends a signal back through motor nerves to muscles in your hand to quickly pull away, often before you even register the pain.
Filtering Dust Particles in the Nose :
Our nose has tiny hairs called cilia and mucous membranes that help filter dust and other particles from the air we breathe in. The mucus traps these particles, and the cilia move them towards the throat, where they can be swallowed or expelled. This process helps protect the lungs from potential damage.
Ways to Take Care of Our Eyes :
Regular Eye Exams : Visiting an eye care professional regularly helps in early detection of vision problems and eye diseases.
Proper Lighting : Ensure that you have adequate lighting while reading or working to reduce eye strain.
Protective Eyewear : Wear sunglasses to protect your eyes from harmful UV rays when outside, and use protective goggles in environments that pose a risk to your eyes.
