Please refer to the Why Do We Fall ill Revision Notes given below. These revision notes have been designed as per the latest NCERT, CBSE and KVS books issued for the current academic year. Students will be able to understand the entire chapter in your class 9th Science book. We have provided chapter wise Notes for Class 9 Science as per the latest examination pattern.
Revision Notes Chapter 13 Why Do We Fall ill
Students of Class 9 Science will be able to revise the entire chapter and also learn all important concepts based on the topic wise notes given below. Our best teachers for Grade 9 have prepared these to help you get better marks in upcoming examinations. These revision notes cover all important topics given in this chapter.
”Disease”( disturbed ease) means being uncomfortable. One or more systems of the body will change, give rise to “Symptoms” ( Cough, loose motions, pus formation, headache, fever, breathlessness, vomiting, fits, unconsciousness, inflammation , swelling and general effects – a Doctor look for the basis of symptoms). Diseases are basically two types- Acute Disease & Chronic Disease
Acute Disease: The disease which lasts for only a short period of time is called Acute Disease Ex. Common Cold.
Chronic Disease: The disease which lasts for long period of time is called Chronic Disease Ex. Tuberculosis.
”Health” is a state of being well enough to function well physically, mentally, and socially.
Causes of Diseases : Most of the diseases have many causes, rather than one single cause, like unclean water, nourishment, genetic differences, genetic abnormalities e.g. Based on the causes diseases are of two types: Non-Infectious Diseases and Infectious Diseases.
Non-Infectious Diseases: Not caused by infectious agents, mostly internal and non- infectious cause. Ex. Cancer
Infectious Diseases: Caused by infectious agents.
Principles of Treatment:
1. Antibiotics: many bacteria make a cell wall to protect themselves, the antibiotic (Penicillin) blocks the bacterial process that builds cell wall and blocks the biochemical pathways. Antibiotics do not work against viral infections. Antiviral medicine is harder than making Antibacterial medicine because Virus has only few biochemical mechanisms of their own. Other medicines bring down fever, reduce pain or loose motions. We can take bed rest to conserve energy. 80
Principles of Prevention : Following three limitation are normally confronted while treating an infectious disease:
• Once someone has disease, their body functions are damaged and may never recover completely.
• Treatment will take time, which means that someone suffering from a disease is likely to be bedridden for some time even if we can give proper treatment.
• The person suffering from an infectious disease can serve as the source from where the infection may spread to other people.
General ways of preventing infectious disease :
• Air-borne – We can prevent exposure by providing living condition that are not overcrowded.
• Water-borne – prevent by providing safe drinking water. This is done by treating the water to kill any microbial contamination.
• Vector-borne – We can provide clean environment, which would not allow mosquito breeding.
Immunity: Even in cells there is repair mechanism called” Immunity”. Immune cells manage to kill off the infectious agents. Smallpox disease is eliminated by developing memory
cells for particular infection by mimics the microbes, called” Vaccine”. The basis of Immunization- if you had smallpox once, there was no chance of suffering from it again. Proper
nutrition is essential to maintain body immunity. There are vaccines against tetanus, diphtheria, whooping cough, measles, polio and many other diseases.
Prevention of disease is better than cure. Hygiene is the basic key to maintain good health.
Important Question and Answer:
Question. Name any two Symptoms of diseases……………………….
Cough& loose motions
Question. Explain with an example the term Vaccine.
Smallpox disease is eliminated by developing memory cells for particular infection by mimics the microbes, called” Vaccine”
Question. The disease which last for only a short period of time is called……………….
Question. Mention the causal organism for Sleeping sickness …………
Question. Cholera is a waterborne disease, mention ………..
Question. Define Health…….
It is astate of being well enough to function well physically, mentally, and socially
Question. Write short notes on Immunity 81
Even in cells there is repair mechanism called” Immunity”. Immune cells manage to kill off the infectious agents
Question. State whether Tuberculosis is aChronic Disease or Acute Disease……
Question. Antibiotics do not work against viral infections, mention ………..