Diseases and First Aid

Solutions for Biology, Class 8, ICSE

Assertion Reason Type Questions

5 questions

Question 2(a)

Assertion (A): Infectious diseases are caused due to the entry of pathogens in the body.

Reason (R): Pathogens are usually microorganisms which can easily spread through air, water and food; and get transmitted from an infected person to a healthy person.

  1. Both A and R are true.
  2. Both A and R are false.
  3. A is true and R is false.
  4. A is false and R is true.
Assertion Reason Type Questions

Answer:

Both A and R are true.

Explanation — Infectious diseases spread from an infected person to a healthy person by the entry of microorganisms/ pathogens. They spread through air, water, food, physical contact, cuts, sexual contact and from insects like mosquitoes, flies, etc.

Question 2(b)

Assertion (A): The disease causing agent/pathogen of 'dengue' is a type of mosquito — Aedes aegypti.

Reason (R): Aedes aegypti spreads germs from a diseased person to a healthy person.

  1. Both A and R are true.
  2. Both A and R are false.
  3. A is true and R is false.
  4. A is false and R is true.
Assertion Reason Type Questions

Answer:

A is false and R is true.

Explanation — Dengue is a mosquito-borne disease caused by the dengue virus. It is spread by a mosquito called Aedes aegypti. Here, the dengue virus is the agent/pathogen, and mosquito Aedes aegypti is the disease causing vector.

Question 2(c)

Assertion (A): 'HIV' is a kind of fungal disease which is usually transmitted through sexual contact or blood transfusion.

Reason (R): The fungus grows and develops in the reproductive organs of humans and get transmitted easily during sexual contact.

  1. Both A and R are true.
  2. Both A and R are false.
  3. A is true and R is false.
  4. A is false and R is true.
Assertion Reason Type Questions

Answer:

Both A and R are false.

Explanation — HIV is a viral disease, not a fungal disease. It weakens the immune system by attacking WBCs. It is transmitted through sexual contact, blood transfusion, and from mother to child during pregnancy, childbirth, or breastfeeding.

Question 2(d)

Assertion (A): Garbage should never be kept in covered bins.

Reason: Covered bins provide suitable conditions for the growth and development of germs as well as serve as breeding places for many vectors.

  1. Both A and R are true.
  2. Both A and R are false.
  3. A is true and R is false.
  4. A is false and R is true.
Assertion Reason Type Questions

Answer:

Both A and R are false.

Explanation — Garbage should be kept in covered bins. Covered bins help prevent the growth of germs and restrict breeding of disease-carrying vectors like flies and mosquitoes.

Question 2(e)

Assertion (A): Diseases like cowpox, smallpox, chickenpox are all caused by the same virus.

Reason (R): The vaccine prepared for smallpox contains the fully virulent, living 'cowpox virus.

  1. Both A and R are true.
  2. Both A and R are false.
  3. A is true and R is false.
  4. A is false and R is true.
Assertion Reason Type Questions

Answer:

A is false and R is true.

Explanation — Diseases like cowpox, smallpox, chickenpox are not caused by the same virus. Cowpox virus and smallpox viruses are similar but not the same. Chickenpox is also caused by a different virus.

Long Answer Questions

4 questions

Question 1

What is Vaccination? Mention the four ways in which vaccines are prepared, giving the name of one disease for which each type of vaccine is used.

Long Answer Questions

Answer:

Vaccination is the practice of artificially introducing germs or germ substances into the body for developing resistance to particular diseases. The material introduced into the body is called the vaccine. Usually, the vaccine is introduced into the body by injection and sometimes orally.
A vaccine can be prepared by any one of the following four methods —

  1. Using killed germs — e.g. TAB vaccine for typhoid.
  2. Using living weakened germs — e.g. the vaccine for measles.
  3. Using fully virulent living germs — e.g. the vaccine for smallpox.
  4. Using Toxoids — e.g. the vaccines used for diphtheria and tetanus.

Question 2

Burns can be superficial burns, deep burns or chemical burns. What emergency care would you suggest in each case.

Long Answer Questions

Answer:

First aid for burns depends on the degree of burns.
In the case of superficial burns, pour cold water over the burnt area. Then dry that portion and cover with sterile dressing.
In the case of deep burns, never use water, and cover the injured part with dressing.
In the case of chemical burns, wash with running water for 10 minutes and then cover with dressing.

Question 3

Write short notes (2-3 sentences) on the following :

(a) Disease

(b) Immunisation

(c) Pathogen

(d) AIDS

(e) Vaccination

(f) Vector

Long Answer Questions

Answer:

(a) Disease — Disease is a departure from normal health through structural or functional disorder of the body. There are two major categories of diseases — Communicable or infectious diseases and Non-Communicable or non-infectious diseases.

(b) Immunization — Immunization is an artificial way of achieving protection from infections by the introduction of dead or weakened germs into one's body. Immunization is a process by which the body of an individual is made resistant to a specific disease by vaccination.

(c) Pathogen — Communicable diseases are caused due to microorganisms such as viruses, bacteria, fungi, worms and protozoa. The disease causing germs are called pathogens. Pathogens spread from one person to other through air, water, food, physical contact, cuts, sexual contact and from insects like mosquitoes, flies, etc.

(d) AIDS — AIDS stands for Acquired Immuno Deficiency Syndrome. It is caused by the HIV virus. It weakens the immunity or self defence mechanism of the human body. AIDS makes the infected person prone to many other infectious diseases. It spreads through sexual contact, blood transfusion and infected syringes.

(e) Vaccination — Vaccination is the practice of artificially introducing germs or germ substances into the body for developing resistance to particular diseases. The material introduced into the body is called the vaccine. When exposed to vaccines, the body makes antibodies and more or less permanent protection from infection is achieved.

(f) Vector — Vectors are those organisms (eg. house flies, mosquitoes, etc.) which carry germs from a source of infection but themselves do not get the infection. For example, mosquitoes while feeding on the blood of a malaria patient, gain the germs in their bodies, and get them transferred in the blood stream of a healthy person whom they bite next.

Question 4

Given below is a crossword puzzle. Read the clues across and clues downward, and fill up the blank squares. Check up your answers with the correct solution given at the end.

CLUES ACROSS (1-6)

  1. The kind of pathogen which causes diseases like common cold and mumps.

  2. These may readily grow in your hair, if you do not wash it regularly.

  3. This is the vaccine for preventing tuberculosis.

  4. The disease pertussis is popularly known as whooping ...............

  5. One of the most common insects that visit our exposed foods and contaminate them.

  6. A disease that weakens body's defence system against infections.

CLUES DOWN (7-11)

  1. Germ or germ substances introduced into the body to prevent occurrence of an infectious disease.

  2. A disease in which the eyes, the skin and the urine turn yellow.

  3. An organ usually affected by tuberculosis.

  4. A disease caused by the bite of an infected dog, and which affects the central nervous system.

  5. Cover this part of your body by a handkerchief while sneezing to prevent droplet infection to others.

Given below is a crossword puzzle. Read the clues across and clues downward, and fill up the blank squares. Check up your answers with the correct solution given at the end. Concise Biology Solutions ICSE Class 8.
Long Answer Questions

Answer:

Given below is a crossword puzzle. Read the clues across and clues downward, and fill up the blank squares. Check up your answers with the correct solution given at the end. Concise Biology Solutions ICSE Class 8.

CLUES ACROSS (1-6)

  1. VIRUS

  2. LICE

  3. BCG

  4. COUGH

  5. FLIES

  6. AIDS

CLUES DOWN (7-11)

  1. VACCINE

  2. JAUNDICE

  3. LUNG

  4. RABIES

  5. MOUTH

Match The Following

1 question

Question 4

Match the items in Column A with those in Column B

Column AColumn B
(a) Malaria(i) Aedes aegypti
(b) Chikungunya(ii) BCG
(c) Poliomyelitis(iii) TAB
(d) Tuberculosis(iv) Salk's vaccine
(e) Typhoid(v) Plasmodium
Match The Following

Answer:

Column AColumn B
(a) Malaria(v) Plasmodium
(b) Chikungunya(i) Aedes aegypti
(c) Poliomyelitis(iv) Salk's vaccine
(d) Tuberculosis(ii) BCG
(e) Typhoid(iii) TAB

Name The Following

1 question

Question 3

Name:

(a) A viral disease caused due to sexual contact with an infected person.

(b) A disease caused due to Plasmodium.

(c) A disease caused by the bite of female Anopheles mosquito.

(d) Two viral diseases caused by mosquito bites.

(e) Any droplet — borne disease.

Name The Following

Answer:

(a) AIDS

(b) Malaria

(c) Malaria

(d) Dengue fever, Chikungunya

(e) Tuberculosis

Objective Type Questions

7 questions

Question 1(a)

A mosquito is a vector for :

  1. Typhoid
  2. Cholera
  3. Malaria
  4. Jaundice
Objective Type Questions

Answer:

Malaria

Reason — Malaria is caused by Plasmodium protozoan that is transmitted by the bite of a female Anopheles mosquito.

Question 1(b)

Dengue is caused by a

  1. Protozoan
  2. Virus
  3. Worm
  4. Fungus
Objective Type Questions

Answer:

Virus

Reason — Dengue is a mosquito-borne disease caused by the dengue virus.

Question 1(c)

The idea of vaccination was conceived by

  1. Charles Darwin
  2. Alexander Flemming
  3. Issac Newton
  4. Edward Jenner
Objective Type Questions

Answer:

Edward Jenner

Reason — The idea of vaccination was conceived by Edward Jenner (1749 - 1823).

Question 1(d)

Which one of the following is not a psychotropic drug?

  1. Morphine
  2. Cocaine
  3. Heroin
  4. Penicillin
Objective Type Questions

Answer:

Penicillin

Reason — Morphine, Cocaine, and Heroin are psychotropic drug. But, Penicillin is an antibiotic.

Question 1(e)

Which one of the following is a communicable disease?

  1. Measles
  2. Cancer
  3. Heart attack
  4. Allergy
Objective Type Questions

Answer:

Measles

Reason — Cancer, heart attack, and allergy are non-communicable diseases whereas measles is a communicable disease.

Question 1(f)

'Prophylaxis' is a significant concept in medical science to prevent humans from many diseases. Specific vaccines for different diseases are prepared by different methods. Which of the following statements are mismatched?

P. Salk's vaccine for typhoid - using toxoids.

Q. BCG vaccine for tuberculosis - using living weakened germs.

R. Salk's vaccine for poliomyelitis - using killed germs.

  1. Only P
  2. Only R
  3. Only P and Q
  4. Only Q and R
Objective Type Questions

Answer:

Only P

Reason — The correct match should be:
TAB vaccine for typhoid - using killed germs.

Question 1(g)

Mohit was playing football in the school playground with his friends. All of a sudden, he fell badly on the ground. His right hand was most likely fractured. What first-aid should be given to him?

  1. Mohit should be laid down on the ground and the fractured part should be moved continuously.
  2. Tie a sling to rest the arm on it.
  3. Apply some alkali, like baking soda on the fractured part.
  4. Apply hot water bag around the fractured part
Objective Type Questions

Answer:

Tie a sling to rest the arm on it.

Reason — In the given case, Mohit should be laid down comfortably, and the fractured arm should not be moved. We should tie a sling upon which the arm can rest.

Short Answer Questions

19 questions

Question 1(a)

Name the two types of diseases on the basis of whether they can be spread or not.

Short Answer Questions

Answer:

The two types of diseases on the basis of their spread are:

  1. Communicable Diseases
  2. Non-communicable Diseases

Question 1(b)

Name the four ways of indirect methods by which infectious diseases can spread.

Short Answer Questions

Answer:

Four ways of indirect methods by which infectious diseases can spread are:

  1. Touching and sharing items used by the infected person
  2. Contaminated food and water or drink
  3. Vectors
  4. Droplets

Question 1(c)

Name the three diseases caused by viruses

Short Answer Questions

Answer:

The three diseases caused by viruses are:

  1. Common Cold
  2. Influenza (The Flu)
  3. HIV/AIDS

Question 1(d)

Name the three diseases in which germs are carried by mosquitoes.

Short Answer Questions

Answer:

The three diseases in which germs are carried by mosquitoes are:

  1. Malaria
  2. Dengue Fever
  3. Chikungunya

Question 1(e)

Name the four methods by which vaccines can be prepared.

Short Answer Questions

Answer:

The four methods by which vaccines can be prepared are:

  1. Using killed germs.
  2. Using living weakened germs.
  3. Using fully virulent living germs.
  4. Using Toxoids

Question 2(a)

Define Health

Short Answer Questions

Answer:

Health is a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.

Question 2(b)

Define Public hygiene

Short Answer Questions

Answer:

Public hygiene refers to the science and practice of protecting and improving the health of a community. It involves proper disposal of human excreta and domestic wastes.

Question 2(c)

Define Vaccine

Short Answer Questions

Answer:

A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease.

Question 2(d)

Define Toxoids

Short Answer Questions

Answer:

Toxoids are extracts of toxins secreted by bacteria and these poisons are made harmless by the addition of formalin to retain the capacity to produce antibodies.

Question 2(e)

Define First aid

Short Answer Questions

Answer:

First aid is the first and immediate assistance given to any person suffering from either a minor or serious illness or injury, with care provided to preserve life, prevent the condition from worsening, or to promote recovery until full medical treatment is available

Question 3(a)

Give two examples of Communicable diseases

Short Answer Questions

Answer:

Influenza, Tuberculosis

Question 3(b)

Give two examples of Non communicable diseases

Short Answer Questions

Answer:

Diabetes, Cardiovascular diseases

Question 3(c)

Give two examples of Viral diseases

Short Answer Questions

Answer:

AIDS, Chickenpox

Question 3(d)

Give two examples of Bacterial diseases

Short Answer Questions

Answer:

Cholera, Typhoid

Question 3(e)

Give two examples of Vectors

Short Answer Questions

Answer:

Mosquitoes, Houseflies

Question 4

What is a non-communicable disease? Answer in brief.

Short Answer Questions

Answer:

Non communicable diseases are those which are not caused by any germ, therefore these diseases cannot spread from an infected person to a healthy person (i.e., they are non transmissible). These may be caused due to improper functioning of the body organs. Example : diabetes, heart attack, etc.

Question 5

What are communicable diseases ?

Short Answer Questions

Answer:

Communicable diseases are those diseases which spread from an infected person to a healthy person by the entry of microorganisms or pathogens. These diseases are caused by the germs known as pathogens. Example: Chicken pox, Malaria, Typhoid, etc.

Question 6

How can we control spreading of diseases by mosquitoes and houseflies ?

Short Answer Questions

Answer:

We can control the spreading of diseases by mosquitoes and houseflies by using repellants, throwing garbage in covered bins, avoid stagnation of water and checking breeding of insects.

Question 7

Public hygiene is equally important as personal hygiene. Give reasons.

Short Answer Questions

Answer:

Public hygiene involves proper disposal of human excreta and domestic wastes. It is equally important as personal hygiene for the following reasons:

  1. Sewage should be chemically treated first before being released into the water bodies to avoid water-borne diseases. There should be proper sewage lines connected to sewage treatment plants.
  2. A healthy environment should be maintained by disposing garbage in covered bins to prevent breeding of flies, avoiding stagnation of water to prevent breeding of mosquitoes.
  3. Contamination of drinking water with faeces (animal or human excreta) should be prevented as it is a major cause of diseases.

Write Full Forms Of The Following

1 question

Question 5

Write full forms for each of the following abbreviations :

(a) AIDS

(b) HIV

(c) WBCs

(d) BCG

(e) TAB

Write Full Forms Of The Following

Answer:

(a) AIDS - Acquired Immune Deficiency Syndrome

(b) HIV - Human Immunodeficiency Virus

(c) WBCs - White Blood Cells

(d) BCG - Bacillus Calmette-Guerin

(e) TAB - Typhoid-paratyphoid A and B