Biology · Ch 10 — Human Health and Diseases
Introduction: Health, Hygiene and the Immune System
Introduction: Health, Hygiene and the Immune System
Can you recall?
- Generally individuals are conscious about their health. So define health.
- Define infectious and non-infectious disease. Give their examples.
Health is far more than simply the 'absence of disease' or physical fitness — the World Health Organization defines it as a state of complete physical, mental and social well-being, not merely the absence of disease or infirmity. Health also reflects how efficiently an organism's metabolism and body functions are running, and hygiene is the science of the rules that protect it: a balanced diet, clean drinking water, personal and community cleanliness, regular exercise, awareness of disease, proper waste disposal and control of disease-carrying vectors.
Every day the body is exposed to foreign agents — bacteria, viruses and other pathogens — yet most people stay healthy most of the time, because the body has a dedicated system that resists these invaders: the immune system. Resistance is the ability to prevent damage or disease through this defence mechanism.
MSBSHSE's HSC Biology syllabus for this chapter draws on the same ground as the NCERT/CBSE Class 12 chapter on human health and disease, so the terms used here serve Maharashtra board and CBSE students alike.