Coughing and sneezing are protective reflexes that help keep the airways clear. A cough usually starts when the throat, windpipe, or lungs are irritated by mucus, dust, smoke, or germs. A sneeze usually starts when the lining of the nose is irritated by pollen, dust, strong smells, or infection.
These reflexes matter because they protect breathing, but they can also send droplets carrying germs into the air.
Key Facts
- A cough is a fast burst of air from the lungs that helps clear the throat and airways.
- A sneeze is a reflex burst of air mainly triggered by irritation inside the nose.
- Mucus traps dust, pollen, and germs so they can be removed from the airway.
- Tiny hairs called cilia move mucus toward the throat or nose for removal.
- Distance = speed × time can estimate how far air or droplets travel in a short burst.
- Covering coughs and sneezes with a tissue or elbow reduces the spread of droplets.
Vocabulary
- Cough
- A cough is a reflex that pushes air out of the lungs to clear irritation or mucus from the airway.
- Sneeze
- A sneeze is a reflex that pushes air out through the nose and mouth when the nose is irritated.
- Mucus
- Mucus is a sticky fluid that traps dust, pollen, and germs in the nose, throat, and airways.
- Cilia
- Cilia are tiny hairlike structures that move mucus and trapped particles out of the respiratory system.
- Droplets
- Droplets are tiny bits of liquid from the mouth or nose that can carry germs when a person coughs, sneezes, talks, or breathes.
Common Mistakes to Avoid
- Coughing or sneezing into your hands, then touching objects. This is wrong because germs can transfer from hands to desks, phones, doorknobs, and other people.
- Thinking a cough always means a serious illness. This is wrong because coughing can also happen from dust, dry air, allergies, exercise, or mild irritation.
- Assuming droplets disappear immediately after a sneeze. This is wrong because some droplets can land on nearby surfaces or remain in the air for a short time.
- Forgetting to wash hands after using a tissue. This is wrong because germs can get onto fingers while handling the tissue and then spread to other surfaces.
Practice Questions
- 1 A sneeze sends droplets forward at about 10 m/s for 0.4 s before they slow down. Using distance = speed × time, how far could the droplets travel in that time?
- 2 A student coughs 6 times in one minute for 5 minutes. How many total coughs occur during that time?
- 3 Explain why coughing or sneezing into your elbow is usually safer than coughing or sneezing into your hands.