ICSE Class 9 Biology
Question 4 of 11
Diseases: Cause and Control — Question 5
Back to all questions(a) Difference between pandemic and sporadic diseases :
| Pandemic diseases | Sporadic diseases |
|---|---|
| A pandemic disease is an outbreak of a disease that occurs over a wide geographic area and affects an exceptionally high proportion of the population. | Sporadic diseases are characterized by the occurrence of isolated individual cases or occasional outbreaks of a disease. |
| Example: AIDS, COVID-19 | Example: Malaria, Cholera |
(b) Difference between communicable and non-communicable diseases :
| Communicable diseases | Non-communicable diseases |
|---|---|
| They are transmitted from infected person to healthy person. | They are non-transmissible. |
| They are caused by germs. | They are not caused by germs. |
| Example: Cholera, Malaria. | Example: Diabetes, beri-beri. |
(c) Difference between allergens and carcinogens :
| Allergens | Carcinogens |
|---|---|
| Any agent that causes allergy is called an allergen. | Any agent that causes cancer is called a carcinogen. |
| Allergens cause the immune system to overreact producing an allergic response. | Carcinogens cause cancer by damaging DNA or interfering with cellular processes, leading to uncontrolled cell growth and the formation of tumors. |
| Example: Dust, Smoke, Pollen | Example: Tobacco, Radiations, Pollutants |
(d) Difference between endemic and epidemic diseases :
| Endemic diseases | Epidemic diseases |
|---|---|
| An endemic disease is found in a certain area only attacking a fewer number of people. | An epidemic disease breaks out and spreads from place to place affecting large number of people at the same time. |
| Example: Yellow fever in African countries, Goitre in Sub-Himalayan region. | Example: Plague in India in 1994, H1N1 influenza pandemic in 2009. |
(e) Difference between pathogen and vector :
| Pathogen | Vector |
|---|---|
| A pathogen is a microorganism or agent that can cause disease in a host organism. | A vector is an organism or agent that can transmit a pathogen from one host to another. |
| Pathogen are generally bacteria, virus, protozoa etc. | Vector are generally mosquitoes, flies, rats, etc. |
| Example: Plasmodium, Mycobacterium tuberculosis | Example: Aedes mosquito, Tsetse fly, Rats. |