NEET Biology Class 9 Chapter 4 Why Do We Fall Ill Short Question And Answers

Why Do We Fall Ill Short Answer Questions

Directions: Give answer in 2-3 sentences.

Question 1. Write a short note on malaria as a disease. Explain its symptoms and control.
Answer:

Malaria is caused by protozoa that lives in water. This parasite enters our body through a female Anopheles mosquito bite which is the vector, visits water to lay eggs, the protozoa enters our blood stream when female mosquito bites us. This protozoa affects our liver and Red blood cells.

Symptoms: Very high fever with periodic shivering, headache and muscular pain.

Control: Use of quinine drug, keeping the surroundings clean, with no stagnant water. Use of mosquito repellent creams, nets, can control the spread of this disease.

Read And Learn More: NEET Class 9 Biology Short Question And Answers

Question 2. Why are infectious diseases called communicable diseases?
Answer:

Infectious diseases are caused by microbes, which can move from one person to another in different ways. As these diseases can be communicated from one person to another, therefore they are called communicable diseases.

For an infectious diseased person in the family following precautions should be taken:

• The surroundings and the house should be clean.
• The infected person should be kept isolated in separate room.
• The clothes and utensils of patient should be sanitized regularly.
• Separate towels and handkerchief should be used by the patient.
• Children should not be allowed to visit the infected person.
• Proper diet and clean, boiled drinking water should be given to the patient.
• A balanced and nutritious diet which will provide lot of energy should be given.
• There should be silence and the patient should be given lot of bed-rest to overcome the infection.

Question 4. What are three limitations for the approach to deal with infectious diseases?
Answer:

The three limitations are:

• If someone has a disease, their body functions are damaged and may never recover completely.
• As the treatment will take time, the person suffering from a disease is likely to be bedridden for some time.
• The infectious person can serve as the source from where the infection may spread to other people.

Question 5. What is antibiotic Penicillin? Give its function.
Answer:

Penicillin antibiotic blocks the bacterial processes that build the cell-wall. Due to this drug, the bacteria is unable to make a protective cell-wall and dies easily. It is used to curve the diseases and infections caused by bacteria.

Question 6. What is AIDS? How does a person get affected with HIV?
Answer:

AIDS is Acquired Immuno Deficiency syndrome, it is caused due to HIV, human immuno deficiency virus. This virus reduces the immunity of human body. Therefore if any microbe enters the body it affects the body thereby killing the person.

Question 7. What are disease specifi means ofprevention?
Answer: The disease-specifi means of prevention are the use of vaccines. The vaccines, are used against tetanus, diphtheria, whooping cough, measles, polio and many others.

Question 8. State two main causes of disease.
Answer:

Two main causes of disease are Immediate cause and

Contributory cause: Immediate cause are the organisms that enter our body and cause disease. Example, virus, protozoa, bacteria. Contributory causes: These are the secondary factors which lead these organisms to enter our body. Example, dirty water, unclean surrounding, contaminated food etc.

Question 9. Bacteria is a cell, antibiotics can kill these bacterias (cell). Human body is also made of cells, how does it affect our body?
Answer:

Antibiotics block the biochemical pathway of bacteria by which it makes a protective cell wall around it. Antibiotic does not allow the bacteria to make this cell wall because of which they die. Human body cell don’t make any cell-wall so antibiotics cannot have any such effect an our body.

Question 10. What are antibiotics? Name the scientist who first discovered antibiotics. Also give name of this antibiotics. What do you mean by vaccination? Who first conceived the idea of vaccination?
Answer:

Antibiotics are the chemicals secreted by microorganisms (e.g., fungi, bacteria), that kill or hinder the growth of certain other microorganisms such as bacteria. Sir Alexander Flemming; Penicillin.

Vaccination is the technique to develop immunity in individuals without infection. Edward Jenner first conceived the idea of vaccination.

Question 11. Name any two ways through which infectious diseases spread?
Answer:

• Through water
• Through sexual contact.

Question 12. Name two diseases that spread through water.
Answer: Cholera, Amoebic dysentry.

Question 13. After eating food, number of people complained of nausea, vomiting, abdominal pain, and loose stools with blood and mucus. Name the disease they are suffering from. Also, name the causative organism.
Answer: Diarrhoea, Bacteria Escherichia coli or Shigella, Salmonella etc.

Question 14. Mention the modes of transmission of tuberculosis.
Answer: Tuberculosis is transmitted directly through sputum of infected person by sneezing, coughing, or spitting and indirectly also (air borne disease).

Question 15. What kind of effects of chronic diseases have on our health?
Answer: Chronic diseases cause drastic long-term effects on our general health.

Question 16. Name any two acute diseases.
Answer: Cold, typhoid.

Question 17. Mention two diseases that spread through sexual contact.
Answer: Syphilis and AIDS.

Question 18. Give major differences between infectious and noninfectious diseases.
Answer:

Question 19. Name any two diseases which occur due to mosquito bites.
Answer:

1. Malaria
2. Japanese encephalitis.

Question 20. Name the viral disease which is about to be completely irradicated from the world. What are its preventive measures?
Answer:

• Poliomyelitis or Polio.
• It can be prevented through immunization with oral polio vaccine.

Question 21. Name two symptoms of tuberculosis of lungs.
Answer:

• Fever and cough
• Blood-containing sputum.

Question 22. Name the vectors of following diseases:

1. Kala-azar
2. Sleeping sickness
3. Typhus
4. Bubonic plague
5. Malaria
6. Dengue

Answer:

Question 23. Name the deficiency diseases caused due to deficiency of

1. Iodine
2. Vitamin B2
   
3. Vitamin D
4. Fluorine
5. Vitamin C
6. Vitamin A
7. Vitamin B12
8. Iron

Answer:

Question 24. Name any three p
Answer:

1. Malaria
2. Amoebic dysentry
3. Sleeping sickness

Question 25. Name one disease caused by Anopheles, Culex and Aedes spp. of mosquitoes. Name the organism that transmits the following diseases:

1. Diarrhea
2. Bubonic plague

Answer:

1. Anopheles – Malaria.

1. Culex – Filariasis.
2. Aedes – Dengue.

2.

1. Diarrhea is transmitted by housefles.
2. Bubonic plague is transmitted by rat fla.

Question 26.

1. A viral disease which generally affects children and causes paralysis of limbs. It is about to be eradicated from the world. Name this disease.
2. Name the programme which was launched globally in 1995-1996 with an aim to eradicate a viral disease from the world.
3. What is the target age group of patients at present in this program?

Answer:

1. Poliomyelitis
2. Pulse Polio Immunisation Programme
3. The target age group at present is extended to all children under 5 years of age.

Question 27. Acute diseases are severe but are less harmful than chronic diseases. Why?
Answer:

Acute diseases are severe but last for short duration. These do not cause long term bad effects on our health. On the contrary, chronic diseases are long lasting and have drastic long term effects on patient’s health.

Question 28.

1. AIDS is a viral disease that spreads by sexual contact. Is there any other way in which this disease can spread?
2. Can you name two diseases which spread by sexual contact but are caused by bacteria instead of virus?
3. Do microorganisms, responsible for causing these diseases, spread by physical contact such as hug or handshake?

Answer:

1. Yes, through blood transfusion from infected person or through use of common needles and syringes.
2. Syphilis and Gonorrhoea, both caused by bacteria.
3. No.

Question 29.

1. Name a group of diseases that last only for short period of time.
Answer: Acute diseases

2. Name any one anatomical or physiological abnormality present in human beings since birth due to:

1. Gene Or Chromosomal Mutations
2. Environmental factors.

Answer:

1. Haemophilia.
2. Cleft p