वृद्धावस्था में मनुष्य की हड्डियां क्यों कमजोर हो जाती है?

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World Geography 3748

Traditional General Knowledge 15616

Sports 4118

Science & Technology 1113

Physics 15584

Modern History 10712

Medieval History 10580

Math 2298

Indian Polity and Constitution 15232

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Indian Economy 2545

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History of the world 3524

Geography 34215

General Science 1404

General Knowledge 128693

General Economics and Indian Economy 2614

Environment and Ecology 2748

Ecology, Environment and Pollution 9

Cytology 3

Current Affairs 19459

Computer 417

Chemistry 57282

Botany 166

Biology 25076

Art & Culture 66

Ancient History 9583

Agriculture & Animal Husbandry 18

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