Chapter Chosen

why do we fall ill

Book Chosen


Subject Chosen


Book Store

Download books and chapters from book store.
Currently only available for.
CBSE Gujarat Board Haryana Board

Previous Year Papers

Download the PDF Question Papers Free for off line practice and view the Solutions online.
Currently only available for.
Class 10 Class 12

List the measures for preventing infectious diseases.

Preventive measures of infectious diseases are -:

(i) We can prevent exposure to air borne diseases i.e., providing living conditions that are not overcrowed.

(ii) We can prevent exposure to water borne microbes by providing safe drinking water free from contamination.

(iii) We can presvent vector-borne infections, by providing clean environment that is abolishing breeding places of mosquitoes and flies.

(iv) Avoid contact in case of disease like measles and chichken pox. Avoiding close physical contact in case of diseases like AIDS.

(v) By making the body immune system strong by having proper and sufficient nourshing food.


What are the different means by which infectious diseases are spread?

Infectious disease can be spread in the following ways : 

(i) By Air - Sneezing or cough little droplets thrown in the air carry micrrobes which can cause the spread. For example in common cold, pneumonia etc.

(ii) Water - Contaminated water carry disease causing microbes which can cause infection o. Example, gut diseases such as cholera.

(iii) Sexual Contact. Diseases such as syphilis or AIDS are transmitted by sexual contact.

(iv) By vectors  These are intermediaries which carry the infectious agents from the patient to the host (normal person). Example, mosquitoes (Female Anopheles mosquito) can cause spread of malaria.


A doctor/nurse/health-worker is exposed to more sick people than others in the community. Find out how she/he avoids getting sick herself.

A doctor/nurse/health-work can avoid getting sick by following these habit -:

(i) Wearing a mask  to cover mouth and nose to avoid infection when in contact with or near a diseased person.

(ii) Using gloves to avoid direct contact with wounds infections and disesed people.       

(iii) Drinking safe water and eating healthy and nutritious food to keep the immune sustem strong.

(iv)  Maintaining personal hygiene  i.e., personal cleanliness, washing hand with dettol/savlon etc. after handling equipment, clothes etc. of patients. 

(v)  Keep the surroundings clean.  





Conduct A survey in your neighbourhood to find out what the three most common diseases are. Suggest three steps that could be taken by your local authorities to bring down the incidence of these diseases.

The three most ommon diseases in the neighbourhood are dysentry, malaria, viral fever.

The three preventive measures that could be taken by the local authorities are 

1. Keeping the area clean i.e., removal of garbage from the streets/ houses and storage in a covered place till it is disposed off. Proper  sanitation and cleaning of drains and proper disposal of sewer water.

2. Cleaning and removal of stagnant water and breeding places of mosquitoes like ditches with stagnant water. Pouring of oil over the stagnant water to kill the larvae of mosquitoes. Spraying of chemicals/smoke in neighbourhood to kill mosquitoes.

3. Ensure supply of safe drinking water. Regular cleaning of the water supply resources. 



What are immediate causes and contributory causes of disease?

(i) Immediate cause of disease are infectious organisms like virus, bacteria, fungi, protozoan etc. 

(ii) Contributory causes of disease are :

(a) Poor health due to lack of good nourishment.

(b) Poor hygiene condition, economic condition due to which one does not get proper and sufficient food.

(c) Genetic difference which make some people more prone to disease than others.