ICSE Class 9 Biology Solutions Chapter 17 Aids to Health

Class 9th ICSE Biology Solutions Chapter 17 Aids to Health

Question 1.
Give one example of each of the following :
(i) Germ killing secretion ……………..
(ii) Germ trapping body secretion ……………..
(iii) Mechanical barrier that prevents entry of germs into the body ……………..
Answer:
(i) Saliva
(ii) Antibodies
(iii) Skin.

Question 2.
Mention if the following statements are True (T) or False (F)
(i) Immune system deals with the germs after they have entered the body.T/F
(ii) Antibodies eat up the germs.T/F
(iii) Human beings can suffer from all those diseases which attack dogs. T/F
(iv) Anti-venin injection against snake bite is an example of artificially acquired passive immunity. T/F
(v) Mother’s antibodies may reach the foetus through placenta. T/F
(vi) A person having once suffered from measles usually gets repeated attacks. T/F
Answer:
(i) F
(ii) T
(iii) F
(iv) T
(v) T
(vi) F.

Progress Check

Question 1.
Define the term ‘prophylaxis’.
……………..
……………..
Answer:
When some germs or germ substances are introduced artificially into the body of some organisms for developing resistance to particular disease. This practice is scientifically called prophylaxis. It is also termed as vaccination.

Question 2.
Name the four categories of material for preparing vaccines.
…………………………
Answer:
(i) Killed germs as TAB vaccine for typhoid and Salk’s vaccine for poliomyelitis.
(ii) Living weakened germs as the vaccine of measles and the freezed dried BCG vaccine for tuberculosis.
(iii) Living fully virulent germs, as for small pox. In this vaccination a person is inoculated with cow-pox virus which is very similar to small-pox virus, cow-pox virus causes only a single pustule to develop rather than multiple pustules of small pox all the body. Vaccination by cowpox vaccine protects from small pox as well.
(iv) Toxoids as for diptheria and tetanus. The toxoids are extracts of toxins secreted by bacteria and these poisons are made harmless by the addition of formalin. Yet, retaining the capacity to produce antibodies. Such extracts are called toxoids.

Question 3.
Name the diseases prevented by :
(i) Salk’s vaccine ……………..
(ii) BCG vaccine ……………..
(iii) DPT vaccine ……………..
Answer:
1. Salk’s vaccine – for Poliomyelitis
2. BCG-for Tuberculosis
3. DPT for Diphtheria, Pertussis and Tetanus.

Progress Check

Question 1.
Correct the following statements if they are false (without changing the first word).
(i) DDT is an antiseptic
……………………………
(ii) Penicillin is a disinfectant.
……………………………………
(iii) Disinfectants are applied on the body.
………………………………….
(iv) Deodorants are both antiseptic as well as disinfectants.
…………………………………………
(v) Alexander Fleming discovered the first sulphonamide.
……………………………………..
(vi) Antibiotics cannot be made synthetically,
…………………………………….
(vii) Sulphonamides are now rarely used
…………………………………….
Answer:
(i) DDT is a disinfectant.
(ii) Penicillin is an antibiotic.
(iii) Disinfectants are applied on spots and places.
(iv) Deodorants are neither antiseptic nor disinfectants.
(v) Alexander Fleming discovered the first antibiotic.
(vi) Antibiotics can be made synthetically.
(vii) True.

Question 2.
List any three uses of antibiotics. ………………………………….
Answer:
Uses of Antibiotics :

1. The best medicine to fight against infections.
2. Some antibiotics are used as food preservatives specially, fresh meat and fish.
3. Some antibiotics are used for controlling plant pathogens.
4. Some antibiotics are used in treating animal feed to prevent internal infections.

Review Questions

A. Multiple Choice Type (Select the most appropriate option in each case)

1. Penicillin is
(a) an antiseptic
(b) a disinfectant
(c) an antibiotic
(d) an anti-toxin
Answer:
(c) an antibiotic

Question 2.
“T” in DTP vaccination stands for
(a) Tuberculosis
(b) Typhoid
(c) Tetanus
(d) Tonsilitis
Answer:
(c) Tetanus

Question 3.
World Health Day is celebrated on
(a) January 15
(b) February 21
(c) April 7
(d) October 10
Answer:
(c) April 7

Question 4.
DPT stands for
(a) Diphtheria, Polio and Tetanus
(b) Diphtheria, Pertussis and Tetanus
(c) Dysentery, Polio and Typhoid
(d) Diphtheria, Polio and Typhoid.
Answer:
(b) Diphtheria, Pertussis and Tetanus

Question 5.
Vaccines are :
(a) An extract of toxins secreted by bacteria.
(b) An extract of dead and weakened microbes.
(c) Strong chemicals obtained from fungi.
(d) Chemicals that are applied on the skin to kill bacteria.
Answer:
(b) An extract of dead and weakened microbes.

B. Very Short Answer Type

Question 1.
Name the following :
(a) The drug based on arsenic compound, produced in 1910 which killed germs of syphilis.
(b) The antibiotic that was discovered first.
(c) The category of immunity required in the treatment of snake-bite.
(d) Any four antiseptic, any two disinfecetants and any two antibiotics.
(e) The vaccine that helps to produce immunity against Polio.
Answer:
(a) Salvarson
(b) Penicillin
(c) Antivenine.
(d) Antiseptic. Carbolic acid, tincture iodine, lysol and potassium permanganate.
Disinfectants. Phenol, formalin, bleaching powder and lime. Antibiotics. Penicillin, chloramphenicol, streptomycin and neomycin.
(e) Salk’s Vaccine helps to produce immunity against polio.

Question 2.
Write the full forms of:
(i) AIDS,
(ii) BCG,
(iii) DPT vaccine
(iv) WHO
Answer:
(i) AIDS – Acquired Immune Deficiency Syndrome.
(ii) BCG – Bacillus of Calmette and Guerin.
(iii) Diphtheria, Pertussis (whooping cough) and Tetanus
(iv) World Health Organization

Question 3.
Give the technical term for the kind of proteins produced in the blood to fight and destroy harmful microbes.
Answer:
Antibodies.

C. Short Answer Type

Question 1.
Mention if the following statements are True (T) of False (F).
(a) Lysol is an antibiotic.
(b) Sweat and tears contain germs-killing substances.
(c) Our body can make only a limited variety of different antibodies.
(d) Salk vaccine is used against tuberculosis.
(e) Treatment by the use of chemicals is known as allopathy.
(f) Alexander Fleming coined the term “antibiotic” for substances like penicillin.
(g) DDT is a disinfectant.
(h) Vaccine provides the body with Active Immunity.
( i) Penicillin was discovered by Alexander Flemming.
(j) BCG is the vaccine given to babies to help build immunity against three common diseases.
Answer:
(a) False
(b) True
(c) True
(d) False
(e) True
(f) True
(g) False
(h) True
(i) True
(j) False

Question 2.
Differentiate between :
(a) Antiseptic and antibiotic,
(b) Antiseptic and disinfectant,
(c) Disinfectant and deodorant,
(d) Vaccination and Sterilisation,
(e) Active immunity and passive immunity,
(f) Innate immunity and acquired immunity.
Answer:
(a)

Antiseptic	Antibiotic
1. These are chemicals.	1. These are produced by the micro-organisms.
2. These are applied on the body surface to’ kill or prevent the growth of micro-organisms.	2. These are taken orally or in the form of injections to cure the disease caused by microorganisms.
3. Tincture iodine, carbolic acid and Lysol etc. are examples.	3. Penicillin, streptomycin and chloramphenicol etc. are examples.

(b)

Antiseptic	Disinfectant
1. These are chemical substances which are applied on the body to kill or prevent the growth of micro organisms.	1. These are chemical substances which are applied on spots and places where micro-organisms thrive and multiply.
2. Mild concentrations are used.	2. These are used in very strong concentrations.
3. Carbolic acid and tincture iodine are the examples.	3. DDT and formalin are the examples.

(c)

Disinfectant	Deodorant
1. These are the chemical substances which are applied on spots and places where germs thrive and multiply.	1. These are the substances used to destroy or mask unpleasant odour.
2. Bleaching powder and DDT are the examples.	2. Potassium permanganate and H2O2 are the examples.

(d)

Vaccination	Sterilisation
1. It is the process of injecting killed or weakened pathogens in the body to prevent infection.	1. It is the process of killing the germs by heating or steaming.

(e)

Active Immunity	Passive Immunity
1. The antibodies are produced by the body itself.	1. The antibodies are injected from outside.
2. It is long-lasting.	2. It is for short-time.

(f)

Innate Immunity	Acquired Immunity
1. It is present from the birth of the individual.	1. It is acquired after the birth of an individual.
2. It is genetic in origin.	2. It is non-genetic.
3. It is inheritable.	3. It is non-inheritable.

Question 3.
Name any three vaccines and the diseases for which they provide immunity.
Answer:

1. DPT – Diphtheria, Pertussis and Tetanus.
2. BCG – Bacillus of Calmette and Guerin.
3. Salk’s vaccine – Poliomyelitis.

Question 4.
Given below are the groups of certain substances of particular categories. Mention the category of each group and identify the wrong example giving reason.
(a) Lysol, benzoic acid, DDT, mercurochrome.
(b) Formalin, iodine, lysol, phenol.
(c) BCG DTP, ATP, TAB.
(d) Tears, skin, nasal secretion, HCI (in stomach).
Answer:
(a) Lysol, benzoic acid, mercurochrome are antiseptics while DDT is disinfectants.
(b) Formalin, iodine, phenol is disinfectants while iodine, is antibiotics.
(c) BCG DTP, TAB’are vaccine ATP while is compound.
(d) Tears, skin, nasal secretion are body’s natural defences while HCI (in stomach) kills germs that entered through food.

Question 5.
Given below is a table of certain vaccines, the diseases against which they are used and the nature of vaccine. Fill up the gaps 1-10.

Vaccine	Disease (s)	The nature of vaccine
TAB	1. …………	2. …………
Salk is vaccine	2. …………	4. …………
BCG	3. …………	Living weakend germs
Vaccine for measles	Measles	6. …………
Cowpox virus	7. …………	8. …………
Toxoids	9. …………	Extracts of toxins
	10. …………	secreted by bacteri

Answer:

Vaccine	Disease (s)	The nature of vaccine
TAB	1. typhod	2. kills germs
Salk is vaccine	2. polomy	4. kills germs
BCG	3. tuberculosis	Living weakend germs
Vaccine for measles	Measles	6. Living weakend germs
Cowpox virus	7. smallpox	8.Virual germs
Toxoids	9. diphtheric	Extracts of toxins
	10. tetanus	Secerted by baactria

Question 6.
Given below is a scheme of classifying immunity against human diseases. Fill up the blanks 1-9.
Answer:

Question 7.
List any four ways in which the antibiotics are being used.
Answer:

1. Certain antibiotics are used as food preservatives.
2. Some antibiotics are used in treating animal food to prevent internal infections.
3. Some antibiotics are used for controlling plant pathogens.
4. Some antibiotics are used to fight infections.

Question 8.
List the merits of local defence systems.
Answer:
The merits of local defence systems are :

• They are not dependent on previous exposure to infections.
• They start working instantaneously.
• They are effective against a wide range of potentially infectious agents.

Question 9.
Suppose a person develops the disease diphtheria. Comment upon the principle of the treatment he should receive.
Answer:
If someone has actually got a disease diphtheria, injecting pre-prepared antibodies from some other source is helpful. For this, an antibody containing serum is obtained from the blood of horses or rabbit etc. In which the disease is artificially produced in a mild form. Thus, a passive immunisation is done.

Question 10.
What first aid steps would you take in the following cases of accident?
(a) Bleeding from a cut in the skin.
(b) A fractured arm
(c) Stoppage of breathing due to electrical shock.
(d) Burn injuries.
Answer:
The following steps are taken during
(a) Bleeding from a cut in the skin.

• Raise the affected part to minimise gravitational flow of blood.
• Wash the cut surface with clean water.
• Press the area with a piece of clean cotton.
• Apply some mild antiseptic if possible.

(b) The following steps are taken if some accident causes fracture in arm.

• Lay the victim comfortably.
• Loosen or remove the shirt.
• Do not move the arm.
• Tie a sling to rest the arm in it.

(c) In case of stoppage of breathing due to electric shock : the following step is followed :
Because breathing must be restored immediately to save life, therefore, artificial means must be applied.
(d)

• Immediately cool the bum area for upto 20 minutes using cool running water from a tap or shower. In the absence of water, any cool clean fluid, e.g., beer, sof drinks can be used.
• Remove any tight clothing, watches ring or jewellery from the injured area, because of risk of swelling.
• Apply a sterile dressing.

D. Long Answer Type

Question 1.
The principle of vaccination is to produce immunity against a disease. Explain.
Answer:
Vaccination is the practice of artificially introducing the weak germs l or germ substances into the body for developing resistance to particular diseases.

Question 2.
“Abnormally large number of WBCs’ in the blood is usually an indication of some infection in our body.” Comment on the statement.
Answer:
WBCs in our blood destroy the harmful germs or pathogens and protect the body from infection. In case of infection the number of WBCs’ is increased to destroy the germs. Hence, a large number of WBCs’ in the blood is an indication of an infection.

Question 3.
Explain briefly the role of the following health aids.
(a) Antiseptics
(b) Disinfectants
(c) Vaccines
Answer:
(a) Antiseptics. Antiseptics are chemical substances which prevent the growth of micro-organisms and other disease causing germs.

(b) Disinfectants. Chemicals which are used for sterilizing non-living objects.

(c) Vaccines. Vaccines are preparations containing heat killed or chemically weakened pathogens, their toxins or toxoids.

ICSE Class 9 Biology Solutions