Class 10 — Biology

Q1. The walls of alveoli are:

✔ Correct: B — Thin moist walls allow rapid diffusion of gases.

Q2. The trachea is kept open by rings of:

✔ Correct: B — C-shaped cartilage rings prevent the trachea from collapsing.

Q3. During exhalation, the diaphragm becomes:

✔ Correct: B — Relaxed diaphragm returns to its dome shape during exhalation.

Q4. Pneumonia is an infection of the:

✔ Correct: B — In pneumonia, alveoli fill with fluid due to bacterial or viral infection.

Q5. In plants, gaseous exchange at night is mainly through:

✔ Correct: B — Stomata in leaves are the main site of gaseous exchange in plants.

Q6. Oxygen is carried in blood mostly by:

✔ Correct: B — Haemoglobin in red blood cells binds and transports oxygen.

Q7. Asthma is a disorder in which airways:

✔ Correct: B — In asthma, bronchioles constrict and swell, making breathing difficult.

Q8. The flap that prevents food from entering the windpipe is:

✔ Correct: B — The epiglottis covers the trachea while swallowing.

Q9. Cellular respiration releases energy in the form of:

✔ Correct: B — Energy from glucose is stored in ATP molecules.

Q10. Bronchitis is the inflammation of:

✔ Correct: B — Bronchitis inflames the bronchial tubes, causing cough and mucus.