1. The Constitution of the World Health Organization (WHO) came into force on April 7, 1948.

2. Significance: This day is now celebrated every year as World Health Day.

3. Objective: To make people aware of the importance of health and encourage them to adopt a healthy lifestyle.

4. Function: The World Health Organization is an international organization that promotes health and improves the health of people around the world.

1. Amazon rain forests have also been called the lungs of planet Earth.

2. These rain forests of South America are the largest and have the highest diversity of tropical rain forests on our planet.

3. They provide 20% of the total oxygen of our planet.