Class 9 - Biology - Why Do We Fall ill? (Worksheet-2)
Fill in the blanks with suitable words.
1. ________ is a state of complete physical, mental and social well-being and not merely an absence of disease or infirmity.
2. A ________ is any physical or functional change from the normal state that causes discomfort, disability or impairs the health of a person.
3. Diseases may be classified as infectious and non-infectious depending upon their causes, or as _______ and _______ depending upon their duration.