9th Std Science Solution in English | Lesson.22 World of Microbes

Lesson 22 World of Microbes

World of Microbes Book Back Answer

I . Choose the correct answer.

1. Which of the following is transmitted through air?

1. Tuberculosis
2. Meningitis
3. Typhoid
4. Cholera

Ans: Tuberculosis

2. One of the means of indirect transmission of a disease is

1. sneezing
2. coughing
3. vectors
4. droplet infection

Ans: vectors

3. Diptheria affects the

1. Lungs
2. Throat
3. Blood
4. Liver

Ans: Throat

4. The primary organ infected during tuberculosis is

1. bone marrow
2. intestine
3. spleen
4. lungs

Ans: lungs

5. Microbes that generally enter the body through nose are likely to affect

1. gut
2. lungs
3. liver
4. lymph nodes

Ans: lungs

6. The organ affected by jaundice is

1. liver
2. lungs
3. kidney
4. brain

Ans: liver

7. Poliomyelitis virus which causes infantile paralysis enters the body through

1. skin
2. mouth and nose
3. ears
4. eye

Ans: mouth and nose

8. Mycology is the branch of biology that deals with the study of

1. algae
2. virus
3. bacteria
4. fungi

Ans: fungi

9. The major constituent of vinegar is

1. citric acid
2. acetic acid
3. oxalic acid
4. hydrochloric acid

Ans: acetic acid

10. Bacteria involved in curd formation is

1. Lactobacillus acidophilus
2. Nitosomonas
3. Bacillus ramous
4. none of the above

Ans: Lactobacillus acidophilus

11. The most fatal form of Malaria is caused by

1. Plasmodium ovale
2. Plasmodium falciparum
3. Plasmodium malariae
4. Plasmodium vivax

Ans: Plasmodium falciparum

12. Mosquito borne viral diseases are

1. malaria and yellow fever
2. dengue and chikungunya
3. filariasis and typhus
4. kala azar and diptheria

Ans: dengue and chikungunya

13. Which one of the following is a pair of viral disease?

1. Filariasis, AIDS
2. Common cold, AIDS
3. Dysentry, Common cold
4. Typhoid, Tuberculosis

Ans: Common cold, AIDS

14. Which of the following disease is spread by animal bite?

1. Pneumonia
2. Tuberculosis
3. Cholera
4. Rabies

Ans: Rabies

15. Severity of disease symptom depends upon

1. number of microbes
2. target organ
3. both a and b
4. none of these.

Ans: both a and b

16. Syphilis is caused by

1. Treponema pallidum
2. Leptospira
3. Pasteurella
4. Vibrio cholerae

Ans: Treponema pallidum

II. Fill in the blanks.

1. __________ break down organic matter and animal waste into ammonia.

Ans: microbes

2. The hyphae with branches form a complex network called __________

Ans: mycelium

3. First antibiotic _________ was developed by _________

Ans : pencillin, Alexander Fleming

4. H1N1 virus causes ___________

Ans: Swine flu

5. _________ is a vector of viral disease dengue.

Ans: Acedes aegypti mosquito

6. Cholera is caused by __________ and malaria is caused by ________

Ans: acteria – Vibrio cholerae, Protozoan parasite -Plasmodium

7. Baker’s yeast is _________

Ans: Saccharomyces cerevisiae

8. The two non symbiotic nitrogen fixing bacteria are __________ and ___________

Ans: Nitrosomonas, Nostoc

9. Typhoid fever is caused by __________

Ans: Salmonella typh

10. __________ vaccine gives considerable protection against tuberculosis.

Ans: BCG (Bacillus Calmette Guerin)

III. Expand the following

IV. Pick out the odd one from the following.

i) AIDS, Retrovirus, Lymphocytes, BCG,

Ans: BCG

ii) Bacterial disease, Rabies, Cholera, Common cold and Influenza

Ans: Cholera

iii) Sporozoites, Merozoites, Trophozoites, Gametocytes (Infective stages of plasmodium in human)

Ans: Gametocytes

V. State whether True or False. If false write the correct statement.

1. Glycogen and oil globules are stored form of food in fungi.

Ans: True

2. One of the differences between virus and viroid is the presence of protein coat in viroid and its absence in virus. 

Ans: False

Correct Ans: protein coat is absent in viroid.

3. Rhizobium, associated with root nodules of leguminous plants fixes atmospheric nitrogen.

Ans: True

4. Lophotrichous is a cluster of polar flagellae.

Ans: True

5. Non- infectious diseases remain confined to the person who develops the disease and do not spread to others.

Ans: True

6. The process of vaccination was developed by Jenner in the year 1796.

Ans: True

7. Hepatitis B is more dangerous than Hepatitis A. b. Common cold, AIDS

Ans: True

VI. Match the following.

VII. Analyze the table and select the option given below that correctly fills the blank.

VIII. Define the following.

1. Pathogen

A pathogen is a biological agent that causes disease to its host.

e.g. bacteria,virus etc.

2. Bacteriophages

Virus that infect bacterial cells.

e.g. T4 bacteriophage.

3. Vaccines

Vaccines are preparation of living or killed microorganisms or their products used for prevention or treatment of diseases

4. Prions

Prions are viral particles which contain only proteins. They do not contain nucleic acid. They are infectious and smaller than viruses.

5. Plasmid

A small extra chromosomal circular DNA called plasmid.It is found in the cytoplasm of bacteria.

IX. Answer the following in brief.

1. Distinguish between Virion and Viroid.

2. Name the vector of the malarial parasite. Mention the species of malarial parasite which cause malignant and fatal malaria.

Anopheles female mosquito is the vector of malarial parasite. Plasmodium falciparum species is malignant and fatal malaria.

3. What is triple antigen? Mention the disease which can be prevented by using the antigen.

Triple antigen is a vaccine used to protect against three disease (DPT).

Dipetheria, Pertussis (wooping cough) and Tetanus can be prevented by using triple antigen.

4. Name the chronic diseases associated with respiratory system.

Tuberculosis,Diptheria,Influenza, Measles are the chronic diseases associated with respiratory system.

5. Name the organism causing diarrhoeal diseases and give one precaution against it.

1. Causative organism -Rota virus
2. Precausion -Proper sanitation and Hygine

6. Name two common mosquitoes and the diseases they transmit.

7. Name the scientist who first discovered penicillin antibiotic. Can you name any other known antibiotic?

1. Alexander fleming
2. Cephalosporin

8. Name the chronic diseases associated with respiratory system.

Tuberculosis,Diptheria,Influenza, Measles are the chronic diseases associated with respiratory system.

9. Name the organism causing diarrhoeal diseases and give one precaution against it.

1. Causative organism -Rota virus
2. Precausion -Proper sanitation and Hygine

10. Name two common mosquitoes and the diseases they transmit.

11. Name one disease that is transmittedby houseflies. Mention their causative pathogen.

12. Sanjay had an attack of chicken pox and has just recovered. The health officer of his locality says that the disease would not occur again for him. What would be the reason for this?

Sanjay got natural active immunity from Chicken box virus that is .It is a type of aquired immunity in which the body produces its own antibodies against disease causing agent.

13. A baby is suffering from diarrhoea, while other babies in the same locality do not. Mention the possible causes that you think. What would be the possible solutions for this?

possible causes for diarrhoea is drink of contaminated water and unhygienic contaminated food. This result infection of intestine proper sanitation and hygiene would be possible solutions for this

X. Assertion and Reason.

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of reason (R) is given just below it. Mark the correct statement as.

1. If both A and R are true and R is correct explanation of A
2. If both A and R are true but R is not the correct explanation of A
3. If A is true but R is false
4. If both A and R are false.

1. Assertion: Chicken pox is a disease indicated by scars and marks in the body.
   Reason: Chicken pox causes rashes on face and further spreads throughout the body.

Ans: If both A and R are false.

2. Assertion: Dengue can be treated by intake of antibiotics.
    Reason: Antibiotics blocks the multiplication of viruses.

Ans: If both A and R are true and R is correct explanation of A

3. Assertion : A patient with cholera is given oral rehydration therapy for rapid replacement of fluid and electrolytes.
   Reason : Cholera can be diagnosed by the microscopic examination of the stool to identify the bacteria.

Ans: If both A and R are true but R is not the correct explanation of A

XI. Higher Order Thinking Skills.

1. Suggest precautionary measures you can take in your school to reduce the incidence of infectious disease.

2. Tejas suffered from typhoid while, Sachin suffered from tuberculosis. Which disease could have caused more damage and why?

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