Q1Multiple choice
Which one of the following is not a viral disease?
- (a)Dengue
- (b)AIDS
- (c)Typhoid
- (d)Influenza
Show answer
(b) AIDS
(a) Dengue
(c) Typhoid
Chapter 13 – Why Do We Fall Ill
Class 9 Science · 39 questions · 39 with answers
Questions
Q2Multiple choice
Which one of the following is not a bacterial disease?
- (a)Cholera
- (b)Tuberculosis
- (c)Anthrax
- (d)Influenza
Show answer
(d) Influenza
Q3Multiple choice
Which one of the following disease is not transmitted by mosquito?
- (a)Brain fever
- (b)Malaria
- (c)Typhoid
- (d)Dengue
Show answer
(c) Typhoid
Q4Multiple choice
Which one of the following disease is caused by bacteria?
- (a)Typhoid
- (b)Anthrax
- (c)Tuberculosis
- (d)Malaria
Show answer
(d) Malaria
Q5Multiple choice
Which one of the following diseases is caused by protozoans?
- (a)Malaria
- (b)Influenza
- (c)AIDS
- (d)Cholera
Show answer
(a) Malaria
Q6Multiple choice
Which one of the following has a long term effect on the health of an individual?
- (a)Common cold
- (b)Chicken pox
- (c)Chewing tobacco
- (d)Stress 16-04-2018
Show answer
(c) Chewing tobacco
Q7Multiple choice
Which of the following can make you ill if you come in contact with an infected person?
- (a)High blood pressure
- (b)Genetic abnormalities
- (c)Sneezing
- (d)Blood cancer
Show answer
(c) Sneezing
Q8Multiple choice
AIDS cannot be transmitted by
- (a)sexual contact
- (b)hugs
- (c)breast feeding
- (d)blood transfusion
Show answer
(b) hugs
Q9Multiple choice
Making anti-viral drugs is more difficult than making anti-bacterial medicines because
- (a)viruses make use of host machinery
- (b)viruses are on the border line of living and non-living
- (c)viruses have very few biochemical mechanisms of their own
- (d)viruses have a protein coat
Show answer
(c) viruses have very few biochemical mechanisms of their own
Q10Multiple choice
Which one of the following causes kala-azar?
- (a)Ascaris
- (b)Trypanosoma
- (c)Leishmania
- (d)Bacteria
Show answer
(c) Leishmania
Q11Multiple choice
If you live in a overcrowded and poorly ventilated house, it is possible that you may suffer from which of the following diseases
- (a)Cancer
- (b)AIDS
- (c)Air borne diseases
- (d)Cholera
Show answer
(c) Air borne diseases
Q12Multiple choice
Which disease is not transmitted by mosquitoes?
- (a)Dengue
- (b)Malaria
- (c)Brain fever or encephalitis
- (d)Pneumonia
Show answer
(d) Pneumonia
Q13Multiple choice
Which one of the following is not important for individual health?
- (a)Living in clean space
- (b)Good economic condition
- (c)Social equality and harmony
- (d)Living in a large and well furnished house WHY DO WE FALL ILL 75 16-04-2018
Show answer
(d) Living in a large and well furnished house WHY DO WE FALL ILL 75 16-04-2018
Q14Multiple choice
Choose the wrong statement
- (a)High blood pressure is caused by excessive weight and lack of exercise.
- (b)Cancers can be caused by genetic abnormalities
- (c)Peptic ulcers are caused by eating acidic food
- (d)Acne in not caused by staphylococci
Show answer
(c) Peptic ulcers are caused by eating acidic food
Q15Multiple choice
We should not allow mosquitoes to breed in our surroundings because they
- (a)multiply very fast and cause pollution
- (b)are vectors for many diseases
- (c)bite and cause skin diseases
- (d)are not important insects
Show answer
(b) are vectors for many diseases
Q16Multiple choice
You are aware of Polio Eradication Programme in your city. Children are vaccinated because
- (a)vaccination kills the polio causing microorganisms
- (b)prevents the entry of polio causing organism
- (c)it creates immunity in the body
- (d)all the above
Show answer
(c) it creates immunity in the body
Q17Multiple choice
Viruses, which cause hepatitis, are transmitted through
- (a)air
- (b)water
- (c)food
- (d)personal contact
Show answer
(b) water
Q18Multiple choice
Vectors can be defined as
- (a)animals carry the infecting agents from sick person to another healthy person
- (b)microorganisms which cause many diseases
- (c)infected person
- (d)diseased plants
Show answer
(a) animals carry the infecting agents from sick person to another healthy person
Q19Multiple choice
Give two examples for each of the following
- (a)Acute diseases
- (b)Chronic diseases
- (c)Infectious diseases
- (d)Non-infectious diseases
Show answer
(a) Acute diseases
(b) Chronic diseases
(c) Infectious diseases
(d) Non-infectious diseases
Q20Short answer
Name two diseases caused by Protozoans What are their causal organisms?
Show answer
(i) Sleeping sickness caused by Trypanosoma / Malaria by plasmodium (ii) Kala-azar caused by Leishmania
Q21Short answer
Which bacterium causes peptic ulcers? Who discovered the above pathogen for the first time? 16-04-2018
Show answer
(i) Helicobactor pylori (ii) Marshall and Warren.
Q22Short answer
What is an antibiotic? Give two examples
Show answer
Antibiotic is a chemical substance that kill bacteria, secreted by micro- organisms which can kill the pathogens. Examples, Penicillin and Streptomycin.
Q23Multiple choice
Fill in the blanks
- (a)Pneumonia is an example of ——— disease.
- (b)Many skin diseases are caused by———.
- (c)Antibiotics commonly block biochemical pathways important for the growth of ———.
- (d)Living organisms carrying the infecting agents from one person to another are called ———.
Show answer
(a) Pneumonia is an example of ——— disease.
(b) Many skin diseases are caused by———.
(c) Antibiotics commonly block biochemical pathways important for the growth of ———.
(d) Living organisms carrying the infecting agents from one person to another are called ———.
Q24Multiple choice
Name the target organs for the following diseases
- (a)Hepatitis targets———.
- (b)Fits or unconsciousness targets ———.
- (c)Pneumonia targets ———.
- (d)Fungal disease targets ———.
Show answer
(a) Hepatitis targets———.
(b) Fits or unconsciousness targets ———.
(c) Pneumonia targets ———.
(d) Fungal disease targets ———.
Q25Short answer
Who discovered ‘vaccine’ for the first time? Name two diseases which can be prevented by using vaccines.
Show answer
Edward Jenner. Example— Small pox, Polio
Q26Multiple choice
Fill in the blanks
- (a)——— disease continues for many days and causes——— on body.
- (b)———disease continues for a few days and causes no longer term effect on body.
- (c)——— is defined as physical, mental and social well-being and comfort.
- (d)Common cold is——— disease. (e) Many skin diseases are caused by———.
Show answer
(a) ——— disease continues for many days and causes——— on body.
(b) ———disease continues for a few days and causes no longer term effect on body.
(c) ——— is defined as physical, mental and social well-being and comfort.
(d) Common cold is——— disease. (e) Many skin diseases are caused by———.
Q27Multiple choice
Classify the following diseases as infectious or non-infectious.
- (a)AIDS
- (b)Tuberculosis
- (c)Cholera
- (d)High blood pressure (e) Heart disease (f) Pneumonia (g) Cancer
Show answer
(a) AIDS
(b) Tuberculosis
(c) Cholera
(d) High blood pressure (e) Heart disease (f) Pneumonia (g) Cancer
Q28Short answer
Name any two groups of micro-organisms from which antibiotics could be extracted.
Show answer
Bacteria and fungi
Q29Short answer
Name any three diseases transmitted through vectors. WHY DO WE FALL ILL 77 16-04-2018
Show answer
Malaria, Dengue and Kala-azar Long Answer Questions
Q30Multiple choice
Explain giving reasons
- (a)Balanced diet is necessary for maintaining healthy body.
- (b)Health of an organism depends upon the surrounding environmental conditions.
- (c)Our surrounding area should be free of stagnant water.
- (d)Social harmony and good economic conditions are necessary for good health.
Show answer
(a) Balanced diet is necessary for maintaining healthy body.
(b) Health of an organism depends upon the surrounding environmental conditions.
(c) Our surrounding area should be free of stagnant water.
(d) Social harmony and good economic conditions are necessary for good health.
Q31Long answer
What is a disease? How many types of diseases have you studied? Give examples.
Show answer
Hint— When the functioning or the appearance of one or more systems of the body change for the worse the body is said to be diseased. The diseases can be — acute/chronic/ infectious/non infectious. Examples, influenza, tuberculosis, pneumonia, cancer respectively. ANSWERS 145
Q32Long answer
What do you mean by disease symptoms? Explain giving two examples?
Show answer
When the functioning or the appearance of one or more systems of the body will change for the worse, it gives certain abnormal signs of the disease. These visual changes in human beings are called symptoms. Symptoms give indication of the presence of a particular disease. Example (i) Lesions on the skin are the symptoms of chickenpox. Example (ii) Cough is the symptom of lung infection.
Q33Long answer
Why is immune system essential for our health?
Show answer
The immune system of our body is a kind of defense mechanism to fight against pathogenic microbes. It has cells that are specialized to kill infecting microbes and keep our body healthy.
Q34Long answer
What precautions will you take to justify “prevention is better than cure”.
Show answer
Following precautions should be taken for prevention of disease. (1) Maintaining hygienic conditions. (2) Awareness about the disease and causal organism. (3) Balanced diet. (4) Regular medical check up.
Q35Long answer
Why do some children fall ill more frequently than others living in the same locality?
Show answer
Hint— Due to poor immune system, some children fall ill frequently. Balanced diet and proper nutrition for healthy body is required to have a strong immune system.
Q36Long answer
Why are antibiotics not effective for viral disease?
Show answer
Antibiotics generally block the biosynthetic pathways and they block these pathways of the microbes/bacteria. However, viruses have very few biochemical mechanisms of their own and hence are unaffected by antibiotics.
Q37Long answer
Becoming exposed to or infected with an infectious microbe does not necessarily mean developing noticeable disease. Explain.
Show answer
Because of strong immune system our body is normally fighting off microbes. We have cells which are specialised to kill the pathogenic microbes. These cells are active when infecting microbes enter the body and if they are successful in removing the pathogen, we remain disease– free. So even if we are exposed to infectious microbes, it is not necessary that we suffer from diseases.
Q38Long answer
Give any four factors necessary for a healthy person.
Show answer
For a healthy person it is necessary that (i) The surrounding environment should be clean. Air and water borne diseases will not spread. (ii) Personal hygiene prevents infectious diseases. (iii) Proper, sufficient nourishment and food is necessary for good immune system of our body. (iv) Immunisation against severe diseases.
Q39Long answer
Why is AIDS considered to be a ‘Syndrome’ and not a disease? 16-04-2018
Show answer
AIDS causing virus— HIV that comes into the body via, the sexual organs or any other means like blood transfusion will spread to lymph nodes all over the body. The virus damages the immune system of the body and due to this the body can no longer fight off many minor infections. Instead, every small cold can become pneumonia, or minor gut infection can become severe diarrhoea with blood loss. The effect of disease becomes very severe and complex, at times killing the person suffering from AIDS. Hence there is no specific disease symptoms for AIDS but it results in a complex diseases and symptoms. Therefore, it is known as a syndrome. C hapter 14 _lqucpq Multiple Choice Questions