Selina Concise Solutions for ICSE Class 10 Biology Chapter 12 Aids To Health

Exercise 1

Solution A.1.
Answer: (c) An antibiotic
In simple words: This question tests basic knowledge about antibiotics as substances that fight bacterial infections.

📝 Teacher's Note: Ensure students understand the difference between antibiotics (kill bacteria), antiseptics (kill germs on skin), and disinfectants (kill germs on surfaces).

🎯 Exam Tip: Remember that antibiotics are specifically for bacterial infections, not viral infections like common cold.

Solution A.2.
Answer: (c) Tetanus
In simple words: This tests knowledge about tetanus as a serious bacterial disease that can be prevented by vaccination.

📝 Teacher's Note: Explain how tetanus bacteria enters through wounds and affects the nervous system, emphasizing the importance of the tetanus vaccine.

🎯 Exam Tip: Associate tetanus with wounds and cuts, and remember it's part of the DTP vaccine combination.

Solution A.3.
Answer: (c) April 7
In simple words: This tests knowledge about World Health Day being celebrated on April 7th every year.

📝 Teacher's Note: Connect this date to WHO's founding and discuss the importance of global health awareness campaigns.

🎯 Exam Tip: Remember April 7 = World Health Day, organized by WHO (World Health Organisation).

Solution B.1.
Answer:
(a) Salvarsan
(b) Penicillin
(c) Passive Acquired Immunity
(d) Antiseptics – Lysol, Iodine, Boric acid and Carbolic acid; Disinfectants – Cresol and Phenol; Antibiotics – Ampicillin and Penicillin
(e) Oral polio vaccine (OPV)
In simple words: These are important medical terms and examples that students need to memorize for understanding health and disease prevention.

📝 Teacher's Note: Create flashcards for these terms and have students practice categorizing different medical substances by their function.

🎯 Exam Tip: Make sure to spell medical terms correctly and remember the specific examples for each category of health aids.

Solution B.2.
Answer:
(i) Acquired Immuno Deficiency Syndrome
(ii) Bacillus Calmette Guerin
(iii) Diphtheria, Pertussis and Tetanus
(iv) World Health Organisation
In simple words: These are full forms of important medical abbreviations that are commonly used in health discussions.

📝 Teacher's Note: Help students create mnemonics to remember these abbreviations and their meanings.

🎯 Exam Tip: Write out the full forms clearly and ensure proper spelling, especially for medical terms.

Solution B.3.
Answer: Antibodies which are immunoglobulins are produced in the blood to fight and destroy harmful microbes.
In simple words: Antibodies are like soldiers in our blood that recognize and destroy germs that try to make us sick.

📝 Teacher's Note: Use the analogy of an army defending a castle to explain how antibodies protect our body from invading germs.

🎯 Exam Tip: Remember that antibodies are immunoglobulins and their main function is to fight harmful microbes.

Solution C.1.
Answer:
(a) False
(b) True
(c) False
(d) False
(e) False
(f) False
In simple words: These true/false answers test understanding of basic health concepts and medical facts.

📝 Teacher's Note: Discuss why each statement is true or false to reinforce correct understanding of health concepts.

🎯 Exam Tip: Read each statement carefully and think about the exact meaning before marking true or false.

Solution C.2.
Answer:
(a) Antiseptic is a mild chemical substance which, when applied on the body, kills germs whereas an antibiotic is a chemical substance produced by a micro-organism, which can kill or inhibit the growth of some other disease producing microorganisms.

(b) Antiseptic is a mild chemical substance which, when applied on the body, kills germs whereas a disinfectant is a strong chemical, which is applied on spots and places on the body where germs thrive and multiply.

(c) Disinfectant is a strong chemical, which is applied on spots and places on the body where germs thrive and multiply whereas deodorants are neither antiseptics nor disinfectants; they aerosols used to mask a bad smell.

(d) Vaccination is the introduction of any kind of dead or weakened germs into the body of a living being to develop immunity (resistance) against the respective disease or diseases whereas sterilization is a process of eliminating or killing all the microbes present on a surface, contained in a fluid, in medication, or in a compound such as biological culture media.

(e) Active immunity is the immunity developed by an individual due to a previous infection or antigen which enters his body naturally whereas passive immunity is the immunity provided to an individual from an outside source in the form of "readymade" antibodies.

(f) Innate immunity is the immunity by the virtue of genetic constitutional makeup i.e. it is inherited from parents. It is present in the body without any external stimulation or a previous infection whereas acquired immunity is the resistance to a disease which an individual acquires during his lifetime. It may be the result of either a previous infection or readymade antibodies supplied from outside.
In simple words: These comparisons help distinguish between similar medical terms by explaining their key differences in simple language.

📝 Teacher's Note: Create comparison charts on the board to visually show the differences between these related concepts.

🎯 Exam Tip: Focus on the key distinguishing features when comparing medical terms - mild vs strong, internal vs external, natural vs artificial.

Solution C.3.
Answer:
1. TAB vaccine for typhoid
2. BCG vaccine for measles
3. DTP vaccine for diphtheria, tetanus and whooping cough
In simple words: These are important vaccines that protect against serious diseases by training our immune system to recognize and fight them.

📝 Teacher's Note: Note that BCG is actually for tuberculosis, not measles - this appears to be an error in the source material that should be corrected.

🎯 Exam Tip: Memorize the vaccine-disease pairs accurately as these are frequently asked in exams.

Solution C.4.
Answer:
(a) Lysol, Benzoic acid, DDT, mercurochrome
Antiseptics. DDT is a wrong example for this category as it belongs to disinfectant which is not good for human skin.

(b) Formalin, iodine, Lysol, phenol.
Disinfectants. Iodine is a wrong example as it is an antiseptic.

(c) BCG, DTP, ATP.
Vaccines. ATP is a wrong example as it is used as an energy carrier in the cells of all known organisms.

(d) Tears, skin, nasal secretion, HCl (in stomach).
Germ Killing Secretions. Skin is a wrong example as it is a protective mechanical barrier. It prevents the entry of microorganisms at first place.
In simple words: This exercise helps identify which items don't belong in each category and explains why they are incorrectly grouped.

📝 Teacher's Note: Use this exercise to reinforce proper categorization skills and help students understand why certain items don't fit in specific groups.

🎯 Exam Tip: Always think about the function and properties of each item when categorizing medical substances.

Solution C.5.
Answer:

In simple words: This table shows different types of vaccines and what kind of germ material they contain to protect us from diseases.

📝 Teacher's Note: Explain how different vaccine types work - killed germs are safe but less effective, weakened germs provide better immunity.

🎯 Exam Tip: Learn the specific vaccine types for each disease as this information is often tested in detail.

Solution C.6.
Answer:
1. Innate Immunity
2. Acquired Immunity
3. Specific Immunity
4. Active Acquired Immunity
5. Passive Acquired Immunity
6. Natural Acquired Active Immunity
7. Artificial Acquired Active Immunity
8. Natural Acquired Passive Immunity
9. Artificial Acquired Passive Immunity
In simple words: These are different types of immunity that protect our body - some we're born with, others we develop through disease or vaccination.

📝 Teacher's Note: Draw a flowchart showing how immunity can be classified into natural/artificial and active/passive categories.

🎯 Exam Tip: Understand the classification system - innate vs acquired, then active vs passive, then natural vs artificial.

Solution C.7.
Answer:
(a) antibiotics have a wide use in medicine to fight infections.
(b) Certain antibiotics are used as food preservatives, especially for fresh meat and fish.
(c) Some antibiotics are used in treating animal feed to prevent internal infections.
(d) Some antibiotics are used for controlling plant pathogens.
In simple words: Antibiotics are useful not just for treating sick people, but also for preserving food and protecting animals and plants from diseases.

📝 Teacher's Note: Discuss the broader applications of antibiotics beyond human medicine, including their role in agriculture and food industry.

🎯 Exam Tip: Remember that antibiotics have multiple uses - medical treatment, food preservation, animal health, and plant protection.

Solution C.8.
Answer:
Merits of the Local Defence Systems:
1. Local defence systems start working instantaneously.
2. These systems are not dependent on previous exposure to infections.
3. They are effective against a wide range of potentially infectious agents.
In simple words: Our body's first line of defense works immediately without needing prior experience and can fight many different types of germs.

📝 Teacher's Note: Emphasize how barriers like skin, stomach acid, and tears provide immediate protection unlike antibodies which need time to develop.

🎯 Exam Tip: Focus on the three key advantages: immediate action, no prior exposure needed, and broad spectrum effectiveness.

Solution C.9.
Answer:
• Diphtheria is a serious bacterial infectious disease. It leads to cold, coughing, sneezing and in severe cases if undiagnosed it might result in heart failure or paralysis.
• Treatment includes a combination of medications and supportive care. The most important step is prompt administration of diphtheria toxoid which is made harmless is given intravenously. The harmless toxoid once administered in patient's body triggers the production of antibodies against the pathogens causing diphtheria.
In simple words: Diphtheria is a dangerous bacterial disease that can be treated by giving the patient a harmless version of the toxin to help their body make antibodies.

📝 Teacher's Note: Explain how toxoids work differently from regular vaccines - they use the harmful substances produced by bacteria rather than the bacteria themselves.

🎯 Exam Tip: Remember that diphtheria treatment uses toxoids (harmless toxins) to stimulate antibody production, not killed or weakened bacteria.

Solution C.10.
Answer:
(a) Bleeding from a cut in the skin:
• In case of bleeding, raise the affected part to minimize the blood flow.
• Wash the cut surface with clean water.
• Press the area with a piece of clean cotton and apply some antiseptic.

(b) A fractured Arm:
• Lay the victim comfortably, loosen or remove the clothes from the affected part.
• Do not move the part fractured.
• If the affected limb is an arm, then tie a sling around the neck to rest the arm in it.

(c) Stoppage of breathing due to electrical shock:
• Lay the victim flat on his back and put a pillow or folded towel under his shoulders in a way that his chest is raised and the head thrown back.
• Hold and draw his arms upwards and backwards. This will cause his chest to expand and draw the air.
• Next, fold the victim's arms and press them against the ribs. The air will now be expelled.
• Repeat the two steps at the rate of about 15 times per minute. Continue till the victim starts breathing without any extra help or till the doctor arrives.
In simple words: These are step-by-step instructions for basic first aid to help injured people before professional medical help arrives.

📝 Teacher's Note: Practice these first aid techniques with students using demonstration and role play to build confidence in emergency situations.

🎯 Exam Tip: Learn the specific steps in order and remember key principles like elevating injured parts and not moving fractured bones.

Solution D.1.
Answer: Vaccination is the practice of artificially introducing the germs or the germ substance into the body for developing resistance to particular diseases. Scientifically, this practice is called prophylaxis and the material introduced into the body is called the vaccine. The vaccine or germ substance is introduced into the body usually by injection and sometimes orally (e.g. polio drops). Inside the body, the vaccine stimulates lymphocytes to produce antibodies against the germs for that particular disease. Antibodies are the integral part of our immunity. Their function is to destroy unwanted particles entered in the body. Vaccines give our immunity a signal to produce specific antibodies. Hence, the principle of vaccination is to produce immunity against a disease.
In simple words: Vaccination works like showing our immune system a picture of the enemy so it can recognize and fight the real disease when it comes.

📝 Teacher's Note: Use the analogy of training soldiers by showing them pictures of enemies before battle to explain how vaccines prepare the immune system.

🎯 Exam Tip: Remember the key terms: prophylaxis (prevention), lymphocytes (white blood cells), and the principle that vaccines train immunity.

Solution D.2.
Answer: Whenever a germ or infection invades the body. A signal is sent to the immune system to produce specific antibodies. In order to cope up with the number of germs being multiplied inside the body, white blood cells start multiplying rapidly. This enables them to produce more number of antibodies and invade infection in time. Therefore, "Abnormally, large numbers of WBCs in the blood are usually an indication of some infection in our body".
In simple words: When germs attack our body, white blood cells multiply quickly to fight them, so having many white blood cells usually means there's an infection.

📝 Teacher's Note: Explain how blood tests can detect infections by counting white blood cells, making this concept relevant to medical diagnosis.

🎯 Exam Tip: Remember that increased WBC count = sign of infection because WBCs multiply to fight germs.

Solution D.3.
Answer:
(a) Antiseptics: Antiseptics are mild chemical substances applied to the body, which prevent the growth of some bacteria and destroy others.
Example: Lysol and Iodine

(b) Disinfectants: Disinfectants are chemicals which will kill all micro-organisms they come in contact with. Disinfectants are usually too strong to be used on body.
Example: Cresol and Phenol

(c) Vaccines: Vaccines are the materials used to administer in the body to provide passive immunity. The materials are generally germs or the substances secreted by the germs.
Example: OPV (Oral polio vaccine) and DTP (Diphtheria, Tetanus and Pertussis)
In simple words: Antiseptics are gentle cleaners for our skin, disinfectants are strong cleaners for surfaces, and vaccines are training materials for our immune system.

📝 Teacher's Note: Emphasize the safety aspect - antiseptics are safe for skin, disinfectants are not, and vaccines are given under medical supervision.

🎯 Exam Tip: Remember the strength difference: antiseptics (mild, for body), disinfectants (strong, for surfaces), vaccines (for immunity).

Solution D.4.
Answer: First aid is the immediate care given to a victim of an accident, sudden illness or other medical emergency before the arrival of an ambulance, doctor or other qualified help.

(a) Little toe in the foot is pierced by a thorn and is bleeding:
• In the case of bleeding, raise the affected part to minimise gravitational outflow of blood.
• Wash the cut surface with clean water, press the area with a piece of clean cotton wool, and if possible, apply some mild antiseptic.

(b) An elderly woman walking on the footpath during a hot mid-day has fallen unconscious:
• Immediately lay the woman comfortably on a side of the road.
• Loosen the clothes.
In simple words: First aid means helping someone immediately after an accident or injury, before professional medical help arrives to take over.

📝 Teacher's Note: Stress that first aid is about immediate, temporary help and should always be followed by proper medical care when available.

🎯 Exam Tip: Define first aid clearly and remember the basic principles: stop bleeding, prevent further injury, and keep victim comfortable until help arrives.

• Let fresh air be around the woman.
• Give some fluids to drink to the woman.

(c) A young boy has burnt his finger tip while firing crackers:

• Immediately wash his burnt finger with sufficiently cold water for a few minutes.
• Do not rub the burnt region.
• Apply creams/ointments specially recommended, in case they are readily available.

(d) Your gardener has been bitten by a snake while digging soil in the flower bed:

• Immediately squeeze out some blood from the wound.
• Tie a tourniquet above the site to prevent spreading of venom into the body.