Ahmed had a severe throat infection. After a few days he developed an earache too. What could be the reason for the pain in his ears? Explain.

Mr. Sharma is a 76 year old man. His vision was gradually becoming blurred. He consulted an eye doctor and it was diagnosed as cataract.

(a) Which part of the eye does cataract affect?

(b) Why does the vision become blurred?

Define the term Allele.

In the last century, the human population has increased tremendously. Death rate has reduced and life expectancy has increased. This rapid growth has placed significant pressure on resources. Global cooperation is needed for environmental preservation.

(a) Mention any one reason for reduction in the death rate.

(b) Name any one resource that is under pressure due to population explosion.