GSEB Class 12 Biology Solutions Chapter 8 Human Health and Diseases

GSEB Class 12 Biology Human Health and Diseases Text Book Questions and Answers

 

Question 1. What are the various public health measures, which you would suggest as a safeguard against infectious diseases?
Answer: Public health initiatives are crucial for preventing infectious diseases. Key measures include:

• Garbage: Regular disposal of waste at designated locations. Containers should be thoroughly cleaned and reused or recycled as appropriate.
• Drainage: To prevent the breeding of flies and mosquitoes, drainage systems must be covered. Stagnant water near homes should be removed, and slum areas should be cleaned.
• Water reservoirs: These should be kept covered and disinfected periodically.
• Sewage disposal: Proper treatment of sewage is necessary before its final disposal.
• Public places: Maintaining cleanliness in public areas and periodic fogging are essential.
• Pollution: Strict anti-pollution laws should be enforced.
• Personal hygiene: Emphasizing good personal hygiene habits.
• Drinking water: Ensuring access to contamination-free drinking water.
• Facilities: Providing public toilets and bathrooms.
• Healthcare: Regular medical examinations and timely vaccinations are important.

In simple words: To prevent infectious diseases, it’s vital to manage waste properly, cover drains, keep water sources clean, treat sewage, maintain public hygiene, ensure clean drinking water, provide public facilities, and promote regular health check-ups and vaccinations.

🎯 Exam Tip: Focus on categorizing the measures (e.g., waste management, water safety, personal hygiene) for a structured and comprehensive answer, highlighting their collective impact on disease prevention.

 

Question 2. In which way has the study of biology helped us to control infectious diseases?
Answer: Biological research has significantly advanced the control of infectious diseases. The development and widespread use of vaccines and immunization campaigns have led to the successful eradication of diseases like smallpox. Conditions such as polio, diphtheria, and tetanus are now largely under control due to effective vaccination programs. Modern biotechnology is continuously focused on creating newer and safer vaccines. Furthermore, the availability of a wide range of antibiotics provides effective treatment for numerous infectious ailments.In simple words: Biology has helped control infectious diseases by developing vaccines that eradicated diseases like smallpox and controlled others like polio, and by providing various antibiotics for treatment.

🎯 Exam Tip: When discussing biology's impact, mention specific examples like smallpox eradication and the role of vaccines and antibiotics for a stronger answer.

 

Question 3. How does the transmission of each of the following diseases take place?
a. Amoebiasis
b. Malaria
c. Ascariasis
d. Pneumonia
Answer:
(a) Amoebiasis: This disease is transmitted through the ingestion of contaminated drinking water and food, often due to improper disposal of fecal matter. Houseflies and airborne currents can also carry cysts, and pet animals can contribute to its spread.
(b) Malaria: Transmission occurs when infected female Anopheles mosquitoes inject sporozoites into a person's bloodstream through their saliva.
(c) Ascariasis: This is spread through contaminated food particles, dirty hands, unhygienic taps, and soaps, often due to fecal-oral transmission.
(d) Pneumonia: Transmission typically happens via droplets and aerosols expelled by an infected individual, which are then inhaled by others.In simple words: Amoebiasis spreads through contaminated food and water, malaria via Anopheles mosquitoes, ascariasis through fecal contamination, and pneumonia through respiratory droplets from infected individuals.

🎯 Exam Tip: For each disease, clearly state the primary mode of transmission. Identifying whether it's vector-borne, water-borne, or airborne helps in organizing the information.

 

Question 4. What measure would you take to prevent water-borne diseases?
Answer: To prevent water-borne diseases, several key measures should be adopted:

• Practise personal and public hygienic measures.
• Drink clean water.

In simple words: Preventing water-borne diseases involves practicing good personal and public hygiene and ensuring the consumption of only clean, safe drinking water.

🎯 Exam Tip: Keep the measures practical and directly related to water safety and hygiene. Simple, direct actions are usually the most effective in preventing water-borne illnesses.

 

Question 5. Discuss with your teacher what does 'a suitable gene' means, in the context of DNA
Answer: In the context of DNA vaccines, a "suitable gene" refers to a gene that encodes for an immunogenic protein. This protein, when produced by the host cells, can trigger an immune response without causing disease. When such a gene is integrated into a vector and introduced into an individual, it enables the person to synthesize the immunogenic protein, thereby providing immunity.In simple words: In DNA vaccines, a "suitable gene" is one that instructs the body to make a protein that triggers an immune response, immunizing the person without causing illness.

🎯 Exam Tip: When defining "suitable gene," emphasize its role in producing an immunogenic protein and how this leads to immunity via vector integration, rather than causing disease.

 

Question 6. Name the primary and secondary lymphoid organs.
Answer: The lymphoid organs are categorized into primary and secondary types based on their function in lymphocyte development and immune response. The primary lymphoid organs include the thymus and bone marrow, where lymphocytes mature. Secondary lymphoid organs, such as lymph nodes, spleen, and tonsils, are sites where mature lymphocytes interact with antigens and initiate immune responses.In simple words: Primary lymphoid organs like the thymus and bone marrow are where immune cells mature, while secondary organs such as lymph nodes, spleen, and tonsils are where these cells fight infections.

🎯 Exam Tip: Clearly distinguish between primary (maturation) and secondary (immune response initiation) lymphoid organs and provide at least two examples for each category.

 

Question 7. The following are some well-known abbreviations, which have been used in this chapter. Expand each one to its full form.
1. MALT
2. CMI
3. AIDS
4. NACO
5. HIV
Answer: The full forms of the given abbreviations are:
1. MALT – Mucosal Associated Lymphoid Tissue
2. CMI – Cell-Mediated Immunity
3. AIDS – Acquired Immune Deficiency Syndrome
4. NACO – National AIDS Control Organisation
5. HIV – Human Immunodeficiency VirusIn simple words: These are common acronyms from the chapter: MALT is Mucosal Associated Lymphoid Tissue, CMI is Cell-Mediated Immunity, AIDS is Acquired Immune Deficiency Syndrome, NACO is National AIDS Control Organisation, and HIV is Human Immunodeficiency Virus.

🎯 Exam Tip: Ensure precise spelling and correct capitalization for each abbreviation's full form, as even minor errors can lead to loss of marks.

 

Question 8. Differentiate the following and give examples of each.
a. Innate and acquired immunity
b. Active and passive immunity
Answer:
a. Innate immunity refers to the non-specific defense mechanisms inherently present at birth, offering immediate protection against a wide range of pathogens. In contrast, acquired immunity is a specific type of resistance that an individual develops or gains throughout their lifetime, characterized by memory and specificity for particular antigens.
b. Active immunity involves the production of antibodies by an animal's own body in response to exposure to an antigen, such as through vaccination or natural infection. Passive immunity, however, occurs when ready-made antibodies are directly transferred to an individual to provide immediate, but temporary, protection against foreign agents.In simple words: Innate immunity is present from birth and non-specific, while acquired immunity develops over time and is specific. Active immunity is when your body makes its own antibodies, and passive immunity is when you receive ready-made antibodies.

🎯 Exam Tip: When differentiating, clearly state the key characteristics for each type of immunity (e.g., presence at birth vs. acquired, antibody production vs. transfer) and include examples if requested.

 

Question 9. Draw a well-labelled diagram of an antibody molecule.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एक एंटीबॉडी अणु की संरचना को दर्शाता है, जिसमें दो भारी श्रृंखलाएं और दो हल्की श्रृंखलाएं होती हैं। इन श्रृंखलाओं में एंटीजन बंधन स्थल (antigen binding site) और डाईसल्फाइड बंध (disulphide bonds) स्पष्ट रूप से दिखाए गए हैं, जो एंटीबॉडी के कार्य के लिए महत्वपूर्ण हैं।In simple words: An antibody molecule, also known as an immunoglobulin, has a Y-shaped structure composed of two heavy chains and two light chains, linked by disulfide bonds, with specific sites for binding antigens.

🎯 Exam Tip: For diagrams, ensure all key components are clearly labeled and correctly positioned. Practice drawing common biological structures accurately to maximize scores.

 

Question 10. What are the various routes by which transmission of the human immunodeficiency virus takes place?
Answer: Once the Human Immunodeficiency Virus (HIV) enters the body, it targets macrophages and converts its RNA genome into DNA using reverse transcriptase. This viral DNA integrates into the host's genetic material, directing the infected cells to produce more virus particles, effectively turning macrophages into "HIV factories." Simultaneously, HIV attacks T-lymphocytes, where it also replicates, producing and releasing more viruses that then infect other T-lymphocytes in the bloodstream. This progressive destruction leads to a decline in the number of T-lymphocytes, causing symptoms like fever, diarrhea, and weight loss. Eventually, the immune system becomes severely weakened, making the individual highly susceptible to opportunistic infections from bacteria (e.g., Mycobacterium), viruses, fungi, and parasites like Toxoplasma, ultimately impairing the body's ability to defend itself.In simple words: HIV attacks immune cells like macrophages and T-lymphocytes, forcing them to produce more viruses, which progressively weakens the immune system and leaves the body vulnerable to various infections.

🎯 Exam Tip: When describing the transmission and progression of HIV, clearly explain the role of specific immune cells (macrophages, T-lymphocytes) and the impact of viral replication on immune system function.

 

Question 11. What is the mechanism by which the AIDS virus causes a deficiency of the immune system of the infected person?
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र रेट्रोवायरस के प्रतिकृति चक्र (replication cycle) को दर्शाता है। इसमें दिखाया गया है कि कैसे एक वायरस सामान्य कोशिका को संक्रमित करता है, अपने RNA को DNA में परिवर्तित करता है, होस्ट जीनोम में एकीकृत होता है, और फिर नई वायरल RNA और वायरस कणों का उत्पादन करता है जो अन्य कोशिकाओं को संक्रमित कर सकते हैं। Macrophages, helper T-cells, and certain nerve cells possess specific T-4 (CD-4) antigen receptor sites on their surface. The HIV attaches to these sites and then enters the cells. Once inside, the virus multiplies, and newly formed virus particles bud out, leading to the death of the host cells. These newly released virus particles then target other cells, particularly helper T-cells. Over time, the continuous destruction of helper T-cells causes their numbers to significantly decrease. Since helper T-cells are vital for the proper functioning of the entire immune system, their reduced count results in a severely compromised immune response, leading to immunodeficiency in the infected individual.In simple words: The AIDS virus (HIV) attaches to and infects helper T-cells and other immune cells, multiplying and destroying them. This continuous depletion of helper T-cells cripples the immune system, leading to its deficiency.

🎯 Exam Tip: When explaining the mechanism of immune deficiency in AIDS, clearly state the target cells (helper T-cells, macrophages) and describe how their destruction directly leads to a weakened immune response.

 

Question 12. How is a cancerous cell different from a normal cell?
Answer: Cancer cells exhibit several distinct differences when compared to normal cells:

• They do not differentiate into specialized cell types.
• They grow and disorganize the tissue in which they originate.
• They often have a large nucleus, prominent nucleolus, and increased ribosomes.
• They lose adhesive junctions, allowing them to detach from other cells.
• They contain an abnormal amount of DNA, making them genetically unstable.
• They demonstrate metastasis, meaning they can spread to distant parts of the body.

In simple words: Cancer cells differ from normal cells because they don't specialize, grow uncontrollably, disorganize tissues, have abnormal DNA, lose their adhesive properties, and can spread throughout the body (metastasis).

🎯 Exam Tip: List specific, observable differences in cellular behavior and structure (e.g., differentiation, growth, nuclear features, adhesion, metastasis) to clearly distinguish cancerous from normal cells.

 

Question 13. Explain what is meant by metastasis.
Answer: Metastasis is the biological process by which cancerous cells detach from their primary tumor, invade surrounding tissues, and spread to distant sites in the body through the bloodstream or lymphatic system. These cells then form secondary tumors at new locations, making cancer a systemic disease.In simple words: Metastasis is when cancer cells break away from the original tumor and travel through the blood or lymph to form new tumors in other parts of the body.

🎯 Exam Tip: Define metastasis by emphasizing the "spread to distant sites" and the role of the circulatory or lymphatic systems in this process, highlighting its significance in cancer progression.

 

Question 14. List the harmful effects caused by alcohol/drug abuse.
Answer: Alcoholism describes a severe addiction to alcohol. Individuals struggling with this are termed alcoholics. Intoxication occurs when blood alcohol content reaches approximately 0.1%. Beyond this level, effects on thinking and reflexes are observed. Further consumption can lead to blurred vision, slurred speech, loss of body balance, and other impairments. When blood alcohol levels reach around 80mg/100ml, symptoms like nausea, vomiting, and headaches may manifest. The immediate consequences of alcohol abuse often include reckless behavior, vandalism, and violence.
In addition to these, alcoholism can also lead to:

• Low to moderate doses can cause reckless behaviour, vandalism and violence depression, fatigue, weight fluctuations, etc.
• Excessive doses of drugs may lead to coma and death due to respiratory failure, heart failure, or cerebral hemorrhage.
• A combination of different drugs or alcohol mixed with drugs results in overdosing and even death.

In simple words: Alcohol and drug abuse can lead to physical and mental deterioration, including impaired judgment, organ damage, addiction, and in severe cases, coma or death, often resulting in reckless behavior and social issues.

🎯 Exam Tip: When listing harmful effects, categorize them (e.g., physiological, neurological, behavioral, social) and include severe outcomes like organ failure or death for a comprehensive answer.

 

Question 15. Do you think that friends can influence one to take alcohol/drugs? If yes, how may one protect himself/herself from such an influence?
Answer: Yes, friends can indeed exert significant influence, both positive and negative, on an individual's choices, including the decision to consume alcohol or drugs. Peer pressure, curiosity, or a desire to fit in can lead youngsters to experiment with such substances.
To protect oneself from such negative influences, one can take several steps:

• Education about the harmful effects of alcohol and drugs: Understanding the severe health and social consequences can strengthen resolve.
• Counselling: Seeking guidance from trusted adults, counselors, or mental health professionals can provide coping strategies.
• Immediate professional and medical help: If someone has already started using, early intervention and support from healthcare professionals are crucial for recovery.
• Developing strong refusal skills: Learning to say "no" assertively without feeling guilty or fearing social rejection.
• Surrounding oneself with positive influences: Choosing friends who share healthy values and interests can reduce exposure to drug and alcohol temptations.
• Engaging in constructive activities: Participating in hobbies, sports, or other positive activities can provide a sense of purpose and belonging, reducing the need for substance use.

In simple words: Friends can influence alcohol/drug use; protection involves educating oneself on risks, seeking counseling or professional help, and learning to confidently decline such offers.

🎯 Exam Tip: Emphasize both proactive measures (education, strong refusal skills) and reactive steps (counseling, professional help) to provide a complete answer on protecting oneself from peer influence.

 

Question 16. Why is it that once a person starts taking alcohol or drugs, it is difficult to get rid of this habit? Discuss it with your teacher.
Answer: It becomes challenging to quit alcohol or drug habits primarily because these substances are highly addictive, causing physical and psychological dependence. When a person attempts to stop, they often experience unpleasant withdrawal symptoms such as nausea, vomiting, diarrhea, shivering, muscle twitching, excessive perspiration, and abdominal cramps. These intense physical and mental discomforts make it extremely difficult to resist the urge to consume the substance again to alleviate the symptoms. The mind loses control, fixating solely on obtaining the addictive substance. Therefore, resisting the initial temptation or pressure is the most crucial step to avoid falling into addictive habits and the severe consequences they entail.In simple words: Quitting alcohol or drugs is hard because they're addictive, causing severe physical and mental withdrawal symptoms like nausea and cramps, making it difficult for the person to resist further use.

🎯 Exam Tip: Highlight the concepts of addiction, physical dependence, and the severity of withdrawal symptoms as the main reasons for the difficulty in quitting, demonstrating an understanding of the physiological aspect.

 

Question 17. In your view what motivates youngsters to take to alcohol or drugs’and how can this be avoided?
Answer: Youngsters often begin experimenting with drugs or alcohol out of curiosity or a desire to explore. Over time, this experimentation can escalate into a habit, particularly as a coping mechanism to escape problems or pressures. Teenagers are especially vulnerable to adopting habits like smoking, drinking, or drug use. One of the most effective strategies to protect them is to identify and address the situations or environmental factors that might push an adolescent towards substance abuse.In simple words: Youngsters start alcohol/drug use due to curiosity or to escape problems; prevention involves identifying and addressing the root causes and pressures that lead to such habits.

🎯 Exam Tip: Focus on underlying psychological and social motivations (curiosity, escapism, peer pressure) and provide practical, early intervention strategies for prevention.

GSEB Class 12 Biology Human Health and Diseases Additional Important Questions and Answers

 

Question 1. What do you mean by “Health'?
Answer: Health is defined as a comprehensive state of complete physical, mental, and social well-being, not merely the absence of disease or infirmity.In simple words: Health means feeling good physically, mentally, and socially, not just being free from sickness.

🎯 Exam Tip: Remember to include all three dimensions-physical, mental, and social-when defining health, as per the WHO definition, for a complete answer.

 

Question 2. Who is a healthy person according to you? What affects health generally?
Answer: According to my understanding, a healthy person is someone who experiences a state of complete physical, mental, psychological, and social well-being, rather than simply being free from disease. Health is influenced by various factors, including genetic disorders, infections, and lifestyle choices. To maintain good health, it is essential to follow a balanced diet, practice personal hygiene, engage in regular exercise, and incorporate practices like yoga.In simple words: A healthy person enjoys full physical, mental, and social well-being, affected by genetics, infections, and lifestyle; maintaining health requires good diet, hygiene, exercise, and yoga.

🎯 Exam Tip: When discussing factors affecting health, remember to cover a broad spectrum including genetic, infectious, and lifestyle elements. For maintenance, focus on holistic approaches.

 

Question 3. Complete the following.

Salmonella typhi	(a)
Haemophilus influenzae	(b)
(c)	Common cold
(d)	Elephantiasis

Answer: The completed table is as follows:

**Name**	**Disease**
Salmonella typhi	(a) Typhoid fever
Haemophilus influenzae	(b) Pneumonia
Rhinovirus	(c) Common cold
Wuchereria bancrofti	(d) Elephantiasis

In simple words: This table maps common pathogens to the diseases they cause: Salmonella typhi causes Typhoid fever, Haemophilus influenzae causes Pneumonia, Rhinovirus causes the Common cold, and Wuchereria bancrofti causes Elephantiasis.

🎯 Exam Tip: For matching or completion questions, ensure you know the causative agent for common diseases. Pay attention to specific scientific names and their corresponding illnesses.

 

Question 4. Typhoid is caused by the attack of salmonella Typhi.
a. Is this a virus or bacteria?
b. Which part of the body is affected by this disease?
c. Name the test used for the diagnosis.
d. Who is Typhoid Mary?
Answer:
a. Salmonella Typhi is a bacterium.
b. The alimentary canal (gastrointestinal tract) is primarily affected by typhoid.
c. The Widal test is used for the diagnosis of typhoid fever.
d. "Typhoid Mary" was the nickname given to Mary Mallon, a cook who was an asymptomatic carrier of typhoid. She inadvertently spread the disease to many people for several years through the food she prepared.In simple words: Typhoid is caused by Salmonella Typhi bacteria, affecting the gut, diagnosed by the Widal test, and Typhoid Mary was an asymptomatic carrier who spread it through food.

🎯 Exam Tip: When answering questions about a specific disease, cover its causative agent type, affected body part, diagnostic method, and any notable historical or public health context like "Typhoid Mary."

 

Question 5. "All pathogens are parasites” Why?
Answer: Pathogens are considered parasites because they live inside or on a host organism and cause damage to that host's body. They derive nutrients or resources from the host, often at the host's expense, which is the defining characteristic of parasitism.In simple words: Pathogens are parasites because they live off a host organism, causing it harm and deriving benefits for themselves.

🎯 Exam Tip: When defining a pathogen as a parasite, emphasize the dual aspects: living on/in a host and causing harm or deriving benefit at the host's expense.

 

Question 6. “AIDS and cancer are caused by ignorance”. Anil said to his classmates. Do you agree with the statement?
Answer: I cannot entirely agree with the statement that "AIDS and cancer are caused by ignorance." While ignorance and lack of awareness can certainly contribute to the transmission of AIDS, as it often involves preventable behaviors, the underlying cause of AIDS is the Human Immunodeficiency Virus (HIV). Cancer, on the other hand, is primarily caused by genetic mutations and the action of carcinogens, which can be influenced by lifestyle but are not solely a result of ignorance. Therefore, while education plays a role in prevention and management, it's an oversimplification to attribute both entirely to ignorance.In simple words: While ignorance can worsen AIDS spread, its cause is HIV; cancer stems from genetic mutations and carcinogens. So, attributing both solely to ignorance is an oversimplification.

🎯 Exam Tip: When evaluating a statement, provide a nuanced answer. Acknowledge partial truths (ignorance impacting AIDS spread) but correct factual inaccuracies (cancer's primary cause) to show comprehensive understanding.

 

Question 7. Name the vectors of malaria and dengue fever?
Answer:

• Malaria – Female Anopheles mosquito
• Dengue fever – Female Aedes mosquito

In simple words: The female Anopheles mosquito transmits malaria, while the female Aedes mosquito is the vector for dengue fever.

🎯 Exam Tip: Be precise with the vector's gender (e.g., female Anopheles) as it's often medically significant for disease transmission.

 

Question 8. Taking the little amount of alcohol is good for health. Do you agree with this statement?
Answer: While some medical perspectives suggest that very small amounts of certain types of alcohol might have minimal health benefits, this statement needs careful consideration. The danger lies in the potential for casual use to escalate. What might initially be perceived as a medicine or occasional indulgence can quickly become a habit, leading to increased consumption and eventual addiction. As the proverb states, "prevention is better than cure." Therefore, it is generally advisable to avoid alcohol altogether, even if perceived to have minor health benefits, to prevent the risks of dependency and negative health outcomes.In simple words: While some believe small amounts of alcohol can be healthy, it's risky due to its addictive nature and potential for increased consumption, making complete avoidance generally safer.

🎯 Exam Tip: Address both sides of the argument (potential minor benefits vs. significant risks of addiction). Prioritize the "prevention is better than cure" aspect, emphasizing the dangers of dependency.

 

Question 9. Patients suffering from filariasis suffer, swelling in the lower limbs. Why?
Answer: Patients afflicted with filariasis experience swelling in their lower limbs because the filarial worm, the causative parasite, primarily resides in the lymphatic vessels of the lower extremities. Its presence and activity cause chronic inflammation and obstruction of these lymphatic pathways, leading to impaired lymphatic fluid drainage. This accumulation of fluid results in characteristic and often severe swelling, a condition known as lymphedema, predominantly affecting the lower limbs.In simple words: Filariasis causes swelling in lower limbs because the filarial worms block lymphatic vessels there, leading to fluid buildup and inflammation.

🎯 Exam Tip: Explain the direct link between the parasite's location (lymphatic vessels), its impact (inflammation and obstruction), and the resulting symptom (swelling/lymphedema) for a clear answer.

 

Question 10. What is the importance of MALT in human health and disease?
Answer: MALT stands for Mucosal Associated Lymphoid Tissue. It represents a crucial component of the immune system found in the lining of major tracts throughout the body, including the respiratory, digestive, and urogenital tracts. These lymphoid tissues play a vital role in initiating and carrying out immunological actions against foreign particles, pathogens, and antigens that enter the body through these mucosal surfaces. MALT acts as a first line of defense, preventing infections and maintaining overall human health.In simple words: MALT (Mucosal Associated Lymphoid Tissue) is key for human health because it's a lymphoid tissue in tracts like the gut and lungs that actively fights off foreign invaders entering the body.

🎯 Exam Tip: Define MALT clearly, specify its location in mucosal linings, and highlight its primary function as an immunological defense against foreign particles for a comprehensive answer.

 

Question 11. Nowadays more than 40% of young people use drugs, pan masala, cigarettes etc. There is also an alarming increase in the use of psychedelic drugs by adolescents. In view of this prepare an article showing the after-effects of drug use and its social implications in the community.
Answer:

Addiction and Dependence

Drugs are habit-forming substances that primarily affect the nervous system, leading to both physical and mental changes in an individual. Drug addiction is characterized by the body's dependence on these substances due to prolonged use. While physicians prescribe certain drugs for medical purposes, such as fighting infections or altering mood, misuse can lead to severe consequences. Drugs can be consumed in various ways, including inhalation, oral ingestion, or injection.
Repeated drug use leads to an increased tolerance level in the body's receptors, meaning that gradually, higher doses are required to achieve the desired effect. This escalation often results in high intake and addiction. Without proper counseling and intervention, individuals can become fully dependent on these substances.
If a habitual user attempts to cease drug intake, their body experiences adverse physiological effects known as withdrawal symptoms, indicating physical dependence. These symptoms can range from mild tremors to severe agitation, convulsions, restlessness, anxiety, nausea, vomiting, abdominal cramps, and anorexia, depending on the type of drug abused. Withdrawal symptoms can be severe and even life-threatening, necessitating professional medical help. Dependence also causes individuals to neglect their social responsibilities and personal adjustments, leading to significant social implications within the community.In simple words: Drug use by young people is rising, causing addiction and dependence as the body needs more to feel the effects. Quitting leads to severe withdrawal symptoms, affecting both individual health and social life.

🎯 Exam Tip: When addressing social implications, link drug abuse to broader issues like neglect of responsibilities, strain on relationships, and increased healthcare burden, showing a holistic understanding of the problem.

 

Question 12. Some drugs when taken for a long time cause addiction.
a. What is withdrawal symptom?
b. How can you prevent the addiction?
Answer:
a. Withdrawal symptoms are the adverse physiological and psychological effects experienced by a drug or alcohol-addicted person when they try to discontinue or reduce the use of the addictive substance. These symptoms can include restlessness, anxiety, nausea, vomiting, abdominal cramps, anorexia, and body twitches.
b. Preventing and treating drug or alcoholic addiction involves several strategies:

• Deaddiction centers: These specialized facilities provide structured programs and medical supervision to help individuals safely detox and recover.
• Proper guidance and counseling: Providing ongoing support, therapy, and life skills training helps individuals address the root causes of their addiction and develop healthier coping mechanisms.
• Awareness and education: Educating individuals, especially young people, about the dangers and long-term effects of substance abuse can prevent initiation.
• Peer support groups: Participation in groups like Narcotics Anonymous or Alcoholics Anonymous can offer a supportive community for recovery.
• Family involvement: Family therapy and support can help heal relationships and create a conducive environment for recovery.

In simple words: Withdrawal symptoms are unpleasant physical and mental effects when an addicted person stops using a substance; addiction can be prevented and treated through deaddiction centers, counseling, and proper guidance.

🎯 Exam Tip: For withdrawal symptoms, list several specific physical and psychological manifestations. For prevention, emphasize a multi-faceted approach involving treatment centers, counseling, and education.

 

Question 13. Drugs are habit forming substances. They react with the nervous system affecting individual physically and mentally.
a. Distinguish between psychotropic drugs and psychedelic drugs.
b. Name the source of opium.
c. What do you mean by withdrawal symptoms?
Answer:
a. Psychotropic drugs are substances that primarily act on the brain, influencing mood, perception, and behavior. They can alter a person's state of mind, often used to treat mental health conditions. Psychedelic drugs, a subset of psychotropics, are known for inducing altered states of consciousness, sensory hallucinations, and profound changes in thought and emotion, often leading to a state of relaxation and pleasure.
b. Opium is derived from the opium poppy plant, *Papaver somniferum*.
c. Withdrawal symptoms refer to the range of adverse physiological and psychological effects experienced by a drug-addicted person when they stop or significantly reduce the use of the substance they are dependent on. These symptoms can include restlessness, anxiety, tremors, nausea, vomiting, and abdominal cramps, indicating the body's physical and mental reliance on the drug.In simple words: Psychotropic drugs affect the brain and mood, while psychedelic drugs cause hallucinations and altered states; opium comes from the poppy plant; withdrawal symptoms are the negative effects experienced when an addicted person stops using a drug.

🎯 Exam Tip: When distinguishing drug types, focus on their primary effects on the nervous system. For sources, provide the botanical name if applicable. For withdrawal symptoms, list specific examples to demonstrate understanding.

 

Question 14. How can you prevent your best friend from becoming a drug addict who has started taking drug?
Answer: To help a friend who has started taking drugs and prevent them from becoming addicted, it's crucial to approach the situation with care and support. Here's how one can intervene:

• Understand the ill effects: Educate your friend about the severe consequences of drug use, including deterioration of moral and cultural standards, increased risk of violence, and engagement in antisocial activities.
• Open communication: Have a supportive and non-judgmental conversation about your concerns. Express your care for their well-being.
• Provide proper advice and awareness: Share accurate information about the physiological and psychological dangers of addiction, dispelling any misconceptions they might have.
• Encourage professional help: Strongly suggest seeking help from counselors, therapists, or addiction specialists. Offer to accompany them to appointments if possible.
• Support healthy alternatives: Encourage participation in hobbies, sports, or other positive activities that can provide a sense of purpose and enjoyment without drugs.
• Be a positive influence: Maintain your own healthy lifestyle and avoid environments or activities that promote drug use.
• Seek adult guidance: If your friend is unwilling to listen, consider seeking advice from a trusted adult (parent, teacher, counselor) on how best to help them, while respecting your friend's privacy as much as possible.

In simple words: To help a friend avoid drug addiction, educate them on the harmful effects, offer supportive advice, and encourage them to seek professional help while promoting healthy alternatives.

🎯 Exam Tip: Emphasize empathetic communication and encouraging professional intervention as primary strategies. Highlighting the negative social and personal consequences of drug use can also be impactful.

 

Question 15. What is vaccination? How does it help in producing immunity?
Answer: Vaccination is a process involving the introduction of a preparation containing antigenic proteins of a pathogen, or a weakened/killed pathogen, into the body. This preparation, known as a vaccine, stimulates the immune system without causing the actual disease.
Vaccines help in producing immunity through the following mechanism:

• The vaccines induce quick multiplication of B and T lymphocytes, some of them are stored as memory cells.
• The B-lymphocytes quickly produce antibodies which neutralize the antigen during infection.

Upon vaccination, the immune system recognizes these antigens as foreign and mounts an immune response, producing specific B-lymphocytes and T-lymphocytes. Some of these activated lymphocytes differentiate into long-lived memory cells. If the vaccinated individual is later exposed to the actual pathogen, these memory cells quickly recognize it and trigger a rapid, robust secondary immune response, producing a large number of antibodies and effector T-cells to neutralize the antigen and prevent disease development, thereby conferring immunity.In simple words: Vaccination introduces weakened or harmless parts of a pathogen to the body, stimulating the immune system to produce B and T cells, including memory cells, which can quickly produce antibodies and fight off future infections.

🎯 Exam Tip: Clearly define vaccination as introducing antigens to stimulate an immune response. Explain the role of B and T lymphocytes and memory cells in providing long-term immunity.

 

Question 16. Mention a single word for the following.
a. Spread of cancer cells to a distant site.
b. Abnormal sensitivity to any substance.
c. Cancer-inducing substances.
d. Non-specific proteins preventing virus multiplication.
Answer:
a. Metastasis
b. Allergy
c. Carcinogens
d. InterferonIn simple words: Spreading cancer is metastasis; abnormal sensitivity is allergy; cancer-causing agents are carcinogens; proteins that stop viruses from multiplying are interferons.

🎯 Exam Tip: For single-word answers, ensure the term is precise and directly corresponds to the definition provided. Accuracy in vocabulary is key here.

 

Question 17. Correct the table.

Drugs	Source
i. Opium	Cannabis sativa
ii. LSD	Papaver somniferum
iii. Cocaine	Claviceps purpurea
iv. Charas	Erythroxylum coca

Answer: The corrected table matching drugs with their correct sources is:

**Drugs**	**Source**
i. Opium	Papaver somniferum
ii. LSD	Claviceps purpurea
iii. Cocaine	Erythroxylum coca
iv. Charas	Cannabis sativa

In simple words: This table correctly pairs drugs with their natural sources: Opium from Papaver somniferum, LSD from Claviceps purpurea, Cocaine from Erythroxylum coca, and Charas from Cannabis sativa.

🎯 Exam Tip: Memorize the specific botanical names or sources for common drugs of abuse. This type of matching question tests direct recall of facts.

 

Question 18. Identify the structure.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एक कैनबिनोइड अणु की रासायनिक संरचना को दर्शाता है। इसमें कार्बन, ऑक्सीजन और हाइड्रोजन परमाणु एक चक्रीय व्यवस्था में जुड़े हुए हैं, जो भांग (cannabis) जैसे पौधों में पाए जाने वाले यौगिकों की विशेषता है।

Structure of Cannabinoid molecule

In simple words: The depicted image illustrates the chemical structure of a cannabinoid molecule.

🎯 Exam Tip: For structure identification questions, a clear and precise name is required. If asked, be ready to also mention the plant source or primary effects of the compound.

 

Question 19. Why do sportspersons always caught by authorities for cocaine addiction? (CBSE2008)
Answer: Sportspersons are frequently apprehended by authorities for cocaine addiction primarily due to its potent physiological effects that can enhance performance, albeit dangerously and unfairly.

• Cocaine has a potent stimulating action on the central nervous system.
• It produces a sense of euphoria and increased energy for performance.

This stimulating effect gives users a temporary boost in energy, alertness, and confidence, which can be perceived as a performance advantage in competitive sports. However, the use of such substances is prohibited under anti-doping regulations because it provides an unfair advantage and poses serious health risks. Authorities conduct regular tests to detect these banned substances, leading to the apprehension of those who use cocaine.In simple words: Sportspersons are caught for cocaine use because it's a powerful stimulant that illegally enhances energy and performance, violating anti-doping rules, and is detectable in tests.

🎯 Exam Tip: When explaining why sportspersons use cocaine, focus on its stimulating effects (euphoria, increased energy) and its role as a performance-enhancing drug, which is illegal in sports.

 

Question 20. Hints given in the following table on cancer and the tissues are wrongly arranged. Copy the table and arrange it in correct order.

Name	Tissues
Carcinoma	Lymph node
Sarcoma	WBC
Melanoma	Connective tissue
Leukaemia	Epithelial cells
Lymphoma	Central nervous system
Glioma	Melanocytes

Answer: The correctly arranged table matching cancer types with their associated tissues is:

**Name**	**Tissues**
Carcinoma	Epithelial cells
Sarcoma	Connective tissue
Melanoma	Melanocytes
Leukaemia	WBC (White Blood Cells)
Lymphoma	Lymph node
Glioma	Central nervous system

In simple words: This table correctly matches cancer types with their tissue origins: Carcinoma in epithelial cells, Sarcoma in connective tissue, Melanoma in melanocytes, Leukaemia in white blood cells, Lymphoma in lymph nodes, and Glioma in the central nervous system.

🎯 Exam Tip: For cancer classification, remember the primary tissue type where each cancer originates (e.g., epithelial for carcinoma, connective for sarcoma). This is a fundamental concept in oncology.

Question 21. Cancer can be cured completely by using chemotherapy.
a. Is this statement true?
b. What is chemotherapy?
c. Name any other five types of treatment against cancer.
Answer:
a. Yes, this statement is accurate.
b. Chemotherapy is a medical treatment approach that involves the use of drugs to treat diseases, particularly cancer.
c. Other effective treatment methods for cancer include:
(i) Surgery
(ii) Radiation therapy
(iii) Chemotherapy
(iv) Hormone therapy
(v) Immunotherapy
In simple words: Cancer treatment involves different methods like medicines, surgery, radiation, and hormone therapy, and it can be cured.

🎯 Exam Tip: Focus on understanding the various cancer treatment modalities and their applications for effective responses.

 

Question 22. The diagram shows an important event taking place in an animal body.
ℹ️ चित्र व्याख्या (Diagram Explanation): इस चित्र में एक जानवर के शरीर में वायरस के प्रसार को रोकने की प्रक्रिया को दर्शाया गया है। यह दिखाता है कि कैसे एक संक्रमित कोशिका (जो वायरस से प्रभावित है) अपने आस-पास की स्वस्थ कोशिकाओं को वायरस के संक्रमण से बचाने के लिए इंटरफेरॉन नामक प्रोटीन जारी करती है। इंटरफेरॉन स्वस्थ कोशिकाओं को वायरस गुणन को रोकने वाले एंजाइमों का उत्पादन करने के लिए उत्तेजित करते हैं, जिससे वायरस का आगे बढ़ना रुक जाता है।
a. Identify the process.
b. What are interferons?
c. How do the interferons prevent virus multiplication?
Answer:
a. The depicted process illustrates the prevention of viral replication by interferons.
b. Interferons are a class of non-specific proteins produced by cells, specifically designed to inhibit viral proliferation.
c. Interferons activate the plasma membrane of healthy cells to synthesize several enzymes. These enzymes then block the virus's ability to reproduce within any subsequently infected cells, thereby halting its multiplication.
In simple words: Interferons are special proteins that stop viruses from multiplying in our bodies by making healthy cells resistant to infection.

🎯 Exam Tip: Understanding the role of interferons in innate immunity is key; remember their function as antiviral proteins and how they protect uninfected cells.

 

Question 23. It is said that "Chikungunya" once affected will not affect a person in the next half of his life. As a student of biology, can you justify this statement.
Answer:
This statement is justifiable because, upon initial exposure to the Chikungunya antigen, the body's T-lymphocytes mount an immune response, attacking and eliminating the pathogen. Crucially, a subset of these T-cells differentiates into long-lived memory T-cells. These memory cells reside in lymphoid organs like the lymph nodes and spleen. Should the body encounter the Chikungunya virus again, these memory T-cells rapidly recognize it and trigger a swift, robust antibody production, thereby conferring lifelong immunity against the disease.
In simple words: When you get Chikungunya, your body makes special "memory" cells. These cells remember the virus, so if it tries to infect you again, your body can quickly fight it off, giving you lifelong protection.

🎯 Exam Tip: Emphasize the concept of immunological memory, specifically the role of memory T-cells in providing long-term immunity after primary exposure to a pathogen.

 

Question 24. In 1974, WHO officially launched a global immunisation programme for children to protect them against six preventable diseases. The following diagram shows the vaccination of the disease.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र विश्व स्वास्थ्य संगठन (WHO) द्वारा बच्चों के लिए चलाए गए वैश्विक टीकाकरण कार्यक्रम को दर्शाता है। इसमें एक बच्चे को पोलियो जैसी रोकथाम योग्य बीमारी से बचाने के लिए मौखिक रूप से वैक्सीन दी जा रही है। यह दृश्य बचपन के टीकाकरण के महत्व और विश्व स्तर पर बीमारियों के उन्मूलन के प्रयासों पर प्रकाश डालता है।
a. Name the disease.
b. Name the vaccine.
c. Mention the times for vaccination scheduled by WHO.
Answer:
a. The disease shown is Polio.
b. The vaccine administered is OPV (Oral Polio Vaccine).
c. According to WHO's initial schedule, vaccination was recommended twice yearly from birth up to two years of age. However, in India, the government now provides this vaccination free of cost, twice annually, until the child reaches five years of age.
In simple words: The picture shows a baby getting the polio vaccine by mouth. This vaccine helps protect children from polio, a disease that used to cause paralysis, and it's given regularly to build strong immunity.

🎯 Exam Tip: Be prepared to identify common childhood diseases, their vaccines, and the importance of global vaccination programs for public health.

 

Question 25. In the case of certain diseases like mumps, measles and chickenpox, the secondary immune response gives a life long immunity. Give the scientific reason behind this.
Answer:
When the body encounters pathogens causing diseases such as mumps, measles, or chickenpox, it activates T-lymphocytes to combat the specific antigens. During this primary immune response, some T-cells mature into long-lived memory T-cells. These specialized cells are retained in lymphoid organs like the lymph nodes and spleen. Upon subsequent exposure to the same pathogen, these memory T-cells enable a rapid and potent secondary immune response, characterized by quick antibody production, thereby conferring lifelong immunity against these specific diseases.
In simple words: Diseases like chickenpox give you lifelong immunity because your body creates "memory" immune cells after the first infection. These cells remember the pathogen and can quickly fight it off if you encounter it again.

🎯 Exam Tip: Focus on the concept of immunological memory, distinguishing between primary and secondary immune responses, and the role of memory cells in long-term protection.

 

Question 26. Copy and complete the flow chart on immunity.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह प्रवाह चार्ट प्रतिरक्षा (immunity) के विभिन्न प्रकारों को दर्शाता है। प्रतिरक्षा को मुख्य रूप से दो श्रेणियों में बांटा गया है: सहज प्रतिरक्षा (Innate Immunity) और उपार्जित प्रतिरक्षा (Acquired Immunity)। सहज प्रतिरक्षा में जन्मजात और प्राकृतिक सुरक्षा शामिल होती है, जबकि उपार्जित प्रतिरक्षा को आगे सक्रिय (Active) और निष्क्रिय (Passive) प्रतिरक्षा में विभाजित किया गया है। सक्रिय प्रतिरक्षा प्राकृतिक (जैसे संक्रमण से) या कृत्रिम (जैसे टीकाकरण से) हो सकती है, और निष्क्रिय प्रतिरक्षा भी प्राकृतिक (जैसे मां से बच्चे को) या कृत्रिम (जैसे एंटीबॉडी का इंजेक्शन) हो सकती है।
Answer:
Immunity can be broadly categorized into:
- **Innate Immunity:** This is present from birth and provides non-specific defense.
- **Acquired Immunity:** This develops during an individual's lifetime and is specific. Acquired immunity is further divided into:
(a) **Active Immunity:** Where the body produces its own antibodies. This can be:
(i) Natural (e.g., from infection)
(ii) Artificial (e.g., from vaccination)
(b) **Passive Immunity:** Where antibodies are received from an external source. This can be:
(i) Natural (e.g., maternal antibodies transferred to fetus)
(ii) Artificial (e.g., antibody injections)
In simple words: Immunity is how our body fights sickness. It can be something we are born with (innate) or something we develop over time (acquired). Acquired immunity can be 'active' (when our body makes its own fighters) or 'passive' (when we get fighters from somewhere else).

🎯 Exam Tip: Be able to classify and explain the different types of immunity, providing examples for each category, especially innate vs. acquired, and active vs. passive.

 

Question 27. Copy the diagram and label the following parts. heavy chain, light chain and specific antigen binding site.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एक एंटीबॉडी अणु की संरचना को दर्शाता है, जिसे इम्यूनोग्लोबुलिन भी कहते हैं। इस 'Y' आकार की संरचना में दो लंबी 'भारी श्रृंखलाएँ' (heavy chains) और दो छोटी 'हल्की श्रृंखलाएँ' (light chains) होती हैं, जो एक साथ जुड़ी होती हैं। इसके ऊपरी सिरे पर विशिष्ट 'एंटीजन-बंधन स्थल' (antigen binding site) होते हैं, जहाँ एंटीजन जुड़कर प्रतिरक्षा प्रतिक्रिया को शुरू करते हैं। यह एंटीबॉडी का एक मूल मॉडल है जो शरीर की प्रतिरक्षा प्रणाली में महत्वपूर्ण भूमिका निभाता है।
Answer:
The diagram of the antibody molecule should be drawn and labeled as follows: Identify the two longer polypeptide chains as the 'heavy chains' and the two shorter chains as the 'light chains'. The regions at the tips of the 'Y' shape, formed by both heavy and light chains, are the 'antigen binding sites', where specific antigens attach.
In simple words: This question asks you to draw and label an antibody, which is a Y-shaped protein. You need to show its two heavy chains, two light chains, and the specific spots where antigens (foreign substances) bind.

🎯 Exam Tip: Practicing the diagram of an antibody molecule and correctly labeling its heavy chain, light chain, and antigen binding sites is essential for visual representation questions.

 

Question 28.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एडवर्ड जेनर (Edward Jenner) का है, जो एक प्रसिद्ध वैज्ञानिक और चिकित्सक थे। उन्हें 'प्रतिरक्षा विज्ञान का जनक' (Father of Immunology) माना जाता है। इस चित्र में उनका गंभीर और विचारशील चेहरा दर्शाया गया है, जो उनके महत्वपूर्ण वैज्ञानिक योगदानों को दर्शाता है।
a. Identify the personality.
b. What are his contributions to science?
Answer:
a. The personality identified in the image is Edward Jenner.
b. Edward Jenner is widely recognized as the 'Father of Immunology'. His most significant scientific contribution was the pioneering development of the vaccination process, specifically for smallpox, which laid the foundation for modern vaccinology.
In simple words: The person in the picture is Edward Jenner, known as the "Father of Immunology." He discovered vaccination, which was a huge step in preventing diseases like smallpox.

🎯 Exam Tip: Recognize key figures in biology and their foundational contributions, such as Edward Jenner's role in the development of vaccination.

 

Question 29. Match the following.

Diseases	Pathogens
i. Ascariasis	Entamoeba histolytica
ii. Malaria	Wuchereria bancrofti
iii. Elephantiasis	Ascaris lumbricoides
iv. Amoebiasis	Plasmodium vivax

Answer:
The correct matching of diseases with their respective pathogens is as follows:
(i) Ascariasis - *Ascaris lumbricoides*
(ii) Malaria - *Plasmodium vivax*
(iii) Elephantiasis - *Wuchereria bancrofti*
(iv) Amoebiasis - *Entamoeba histolytica*
In simple words: This question asks you to match diseases with the germs that cause them. For example, malaria is caused by Plasmodium, and ascariasis is caused by Ascaris lumbricoides.

🎯 Exam Tip: Memorize the causative agents (pathogens) for common human diseases to accurately match them in examinations.

 

Question 30. Mention the types of malaria caused by the following species of plasmodium.
i. *Plasmodium vivax*
ii. *Plasmodium malariae*
iii. *Plasmodium ovale*
iv. *Plasmodium falciparum*
Answer:
The various types of malaria, classified by their causative *Plasmodium* species, are detailed below:

Name	Types of fever
*Plasmodium vivax*	Benign tertian, every 48 hrs
*Plasmodium malariae*	Quartan, every 72 hrs.
*Plasmodium ovale*	Mild tertian, every 48 hrs.
*Plasmodium falciparum*	Malignant, every 48 hrs. or every 24 hrs. It is often fatal

In simple words: Different types of malaria parasites cause different kinds of fever patterns. For example, Plasmodium vivax causes fever every two days, while Plasmodium falciparum causes a dangerous form of malaria that can be deadly.

🎯 Exam Tip: Differentiate between the various *Plasmodium* species and the specific malarial fever patterns and severity associated with each.

 

Question 31. Name the fungi causing ringworms in man.
Answer:
The fungi commonly responsible for causing ringworm infections in humans include *Epidermophyton*, *Trichophyton*, and *Microsporum* species.
In simple words: Ringworm, a common skin infection, is caused by specific types of fungi like Epidermophyton, Trichophyton, and Microsporum.

🎯 Exam Tip: Remember the names of the primary fungal genera responsible for dermatophytosis (ringworm) infections in humans.

 

Question 32. Name the causative organisms of typhoid fever. Mention the symptoms and the test which is used for detecting typhoid fever.
Answer:
The causative organism for typhoid fever is *Salmonella typhi*. Common symptoms of typhoid include a persistent high fever, general weakness, abdominal pain, constipation, headaches, and a noticeable loss of appetite. The diagnostic test commonly employed to detect typhoid fever is the Widal test.
In simple words: Typhoid fever is caused by a bacteria called Salmonella typhi. It makes you have a high fever, stomach pain, and feel weak. Doctors use the Widal test to find out if you have it.

🎯 Exam Tip: Be precise with the name of the causative agent for typhoid, its key symptoms, and the specific diagnostic test used.

 

Question 33. For the detection of filariasis, blood is taken only between 10 pm and 5 am. Give reason.
Answer:
For accurate detection of filariasis, blood samples are typically drawn only between 10 PM and 5 AM. This specific timing is crucial because the microfilariae, which are the larval stage of the filarial parasite, exhibit nocturnal periodicity, meaning they migrate into the peripheral bloodstream predominantly during these night hours.
In simple words: To find filarial worms in blood, samples are taken at night (10 PM to 5 AM). This is because the tiny baby worms (microfilariae) are mostly found in the outer blood vessels only during these hours.

🎯 Exam Tip: Understand the concept of nocturnal periodicity in parasitic infections, particularly why blood collection for filariasis diagnosis is time-sensitive.

 

Question 34. *Plasmodium vivax* is a digenetic parasite. Justify your answer.
Answer:
Indeed, *Plasmodium vivax* is classified as a digenetic parasite. This classification is justified because it necessitates two different hosts – humans and mosquitoes – to successfully complete all stages of its intricate life cycle, transitioning between asexual reproduction in humans and sexual reproduction in mosquitoes.
In simple words: Plasmodium vivax is called a digenetic parasite because it needs two different hosts – humans and mosquitoes – to finish its entire life cycle. It can't complete its journey with just one.

🎯 Exam Tip: Define 'digenetic parasite' and clearly identify the two hosts involved in the life cycle of *Plasmodium* species to justify its classification.

 

Question 35. 'Smoking is injurious to health'. This is the slogan seen in all cigarette packets.
a. As said above “is smoking injurious to health?
b. Name the toxic alkaloid seen in it.
c. Give some consequences a smoker has to face in the future.
Answer:
a. Yes, it is unequivocally true that smoking is detrimental to one's health.
b. The primary toxic alkaloid present in tobacco, and thus in cigarettes, is nicotine.
c. The future consequences for a smoker can include a range of severe health issues such as increased risk of various cancers (lung, throat, mouth), cardiovascular diseases, chronic obstructive pulmonary disease (COPD), stroke, and reduced overall life expectancy, among others.
In simple words: Smoking is very bad for your health because of nicotine, a toxic substance in cigarettes. It can lead to serious future health problems like cancer, heart disease, and breathing difficulties.

🎯 Exam Tip: Remember nicotine as the key toxic component in tobacco and be able to list at least three major health consequences of smoking.

 

Question 36. What is AIDS? Write down its causes, transmission, and symptoms. Or Write the name, two symptoms, and important preventive measures of today's deadening disease spread through blood transfusion. Or Where is AIDS reported for the first time? Describe the causes, method of transmission, and control measures of this disease.
Answer:
AIDS, or Acquired Immune Deficiency Syndrome, was first identified in America in 1981.
**Causes of Disease:** This condition results from an infection by the Human Immunodeficiency Virus (HIV).
**Transmission:** HIV primarily spreads through several routes, including unprotected sexual contact, sharing contaminated needles (e.g., among intravenous drug users), blood transfusions, drug use, artificial insemination, and organ transplantation.
**Symptoms of Disease:** Individuals with AIDS typically exhibit symptoms such as swollen lymph nodes, persistent fever, and significant weight loss. A critical characteristic of the disease is a profound weakening of the immune system due to a drastic reduction in helper T-cells, making the person vulnerable to opportunistic infections.
**Treatment:** Currently, there is no definitive cure for AIDS. Antiviral therapies are employed primarily to manage the infection, slow its progression, and enhance immune function.
**Control:** Preventing the spread of AIDS requires widespread awareness and adherence to preventive measures, including comprehensive health education regarding the risks and modes of transmission.
- **Avoiding reuse of syringes:** Used syringes should be disposed of safely after a single use.
- **Screening of blood and organs:** All donated blood, organs for transplantation (such as kidneys, liver, corneas), and growth hormones must undergo rigorous screening for HIV before use.
- **Practicing safe sexual behaviors:** Avoiding multiple sexual partners and consistently using protection can significantly reduce transmission risk.
In simple words: AIDS is a serious disease caused by the HIV virus, which attacks the body's immune system. It spreads through body fluids like blood and during sex. There's no cure, but medicines can help manage it, and preventing its spread relies on education and safe practices.

🎯 Exam Tip: Understand AIDS as an immune deficiency syndrome, its viral cause (HIV), main modes of transmission, key symptoms (especially helper T-cell reduction), and primary prevention strategies.

 

Question 37. Observe the following structure and answer the questions.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र मॉर्फिन (Morphine) की रासायनिक संरचना को दर्शाता है, जो एक शक्तिशाली ओपिओइड एनाल्जेसिक है। संरचना में जटिल चक्रीय रिंग और विशिष्ट कार्यात्मक समूह दिखाए गए हैं जो इसके औषधीय गुणों के लिए जिम्मेदार हैं। यह संरचना अफीम के पौधे से प्राप्त होती है और केंद्रीय तंत्रिका तंत्र पर कार्य करती है।
a. Identify the chemical structure.
b. Name the source.
c. Name the organ which it affects.
Answer:
a. The chemical structure depicted is that of morphine.
b. Morphine is primarily sourced from the poppy plant, *Papaver somniferum*.
c. The main physiological system affected by morphine is the central nervous system (CNS).
In simple words: The image shows the chemical structure of morphine. This substance comes from the poppy plant and mainly affects the brain and spinal cord, which is our central nervous system.

🎯 Exam Tip: Be able to identify the structure of common drugs like morphine, recall their natural sources, and understand their primary target systems in the body.

 

Question 38. Expand ELISA.
Answer:
ELISA stands for Enzyme-Linked Immunosorbent Assay.
In simple words: ELISA is a test used to detect substances like antibodies or antigens in a sample, and its full name is Enzyme-Linked Immunosorbent Assay.

🎯 Exam Tip: Memorize the full form of common acronyms in biology, such as ELISA, and briefly understand their purpose.

 

Question 39. 'Human life is a battlefield.' Justify the statement.
Answer:
The statement 'Human life is a battlefield' can be justified by recognizing that humans are constantly exposed to and challenged by numerous pathogenic organisms, including viruses, bacteria, fungi, and parasites. In this analogy, our bodies act as soldiers, continuously defending against these external invaders that seek to cause disease, making life a continuous struggle for health and survival.
In simple words: Human life is like a battle because our bodies are constantly fighting against harmful germs like viruses, bacteria, and fungi. We are always defending ourselves from sickness.

🎯 Exam Tip: Connect biological concepts of immunity and pathogen exposure to philosophical statements, explaining how the body's defense mechanisms are constantly at work.

 

Question 40. "It is dangerous to take drugs without prescription of a doctor at early months of pregnancy." Justify the statement.
Answer:
Taking drugs without a doctor's prescription, especially during the early months of pregnancy, is highly dangerous due to potential teratogenic effects. Teratogens are substances that can cause developmental abnormalities in an embryo or fetus. Such drug exposure can lead to the rudimentary or incomplete development of vital organs, resulting in the formation of a malformed embryo or birth defects in the child.
In simple words: Taking drugs without a doctor's permission, especially early in pregnancy, is risky because these drugs can harm the developing baby, causing problems with organ growth and leading to birth defects.

🎯 Exam Tip: Understand the concept of teratogens and their significant impact on embryonic development, particularly in the context of drug consumption during pregnancy.

 

Question 41. A doctor noticed a small internal growth in the abdomen of a patient. He suspected it as a cancer.
a. Which biomedical technique enabled the doctor to diagnose the disease?
b. Suggest the methods to treat this disease.
Answer:
a. The doctor could utilize several biomedical techniques for diagnosis, including biopsy, various scanning methods (like CT scans), Magnetic Resonance Imaging (MRI), or sonography, among other relevant diagnostic procedures.
b. Treatment methods for cancer typically involve a combination of approaches such as:
(i) Surgery: Surgical removal of the tumor.
(ii) Radiation Therapy: Using high-energy radiation to kill cancer cells.
(iii) Chemotherapy: Administering drugs to destroy cancer cells.
(iv) Hormone Therapy: Blocking or adding hormones to treat hormone-sensitive cancers.
(v) Immunotherapy: Boosting the body's natural defenses to fight cancer.
In simple words: To diagnose an internal growth like cancer, doctors use tests like biopsies, MRI, or scans. If it's cancer, treatments can include surgery, chemotherapy (drugs), radiation, hormone therapy, or immunotherapy to fight the disease.

🎯 Exam Tip: Be familiar with both diagnostic techniques (biopsy, imaging) and the five main treatment modalities for cancer (surgery, radiation, chemo, hormone, immunotherapy).

 

Question 42. A doctor detected a tumour in the body of a person. The patient feels that he would die soon due to tumour. How can you help him to overcome his fear?. Write your response.
Answer:
To help a patient overcome the fear of dying from a detected tumor, it's crucial to provide clear, empathetic, and factual information. One could explain that not all tumors are cancerous (malignant); many are benign and do not spread to other parts of the body. Reassure the patient that benign tumors are generally not life-threatening and can often be completely and permanently removed through surgical intervention, which is considered a definitive treatment.
In simple words: If a patient is scared about a tumor, reassure them by explaining that not all tumors are cancer. Many are benign and won't spread, and can be completely removed with surgery, which is a permanent fix.

🎯 Exam Tip: Differentiate between benign and malignant tumors and emphasize the importance of accurate medical information and reassurance in patient counseling.

 

Question 43. "The soldiers of a country kill their own king". Similar situation takes place in our body. Find out that process.
Answer:
The process described by the analogy 'The soldiers of a country kill their own king' is analogous to an autoimmune disease in the human body. In these conditions, the body's immune system, which is designed to protect against foreign invaders, mistakenly attacks and destroys its own healthy cells and tissues, treating them as foreign entities.
In simple words: The process where the body's own immune system mistakenly attacks its healthy cells, like "soldiers killing their own king," is called an autoimmune disease.

🎯 Exam Tip: Understand autoimmune diseases as conditions where the immune system loses self-tolerance and attacks the body's own tissues.

 

Question 44. Mention any two measures for prevention and control of alcohol and drug abuse among adolescents.
Answer:
Two key measures for preventing and controlling alcohol and drug abuse among adolescents include:
(i) **Avoiding undue peer pressure:** Adolescents should be educated and empowered to resist negative influences from peers that encourage substance abuse.
(ii) **Seeking professional and medical help:** Encouraging early intervention by seeking guidance from counselors, therapists, or medical professionals for individuals struggling with or at risk of substance abuse.
In simple words: To prevent drug and alcohol abuse in young people, teach them to say no to peer pressure and encourage them to get help from doctors or counselors if they need it.

🎯 Exam Tip: Focus on both social (peer pressure) and professional intervention as practical measures for addressing substance abuse in youth.

 

Question 45. Given below are pairs of disease and causative organisms. Which one out of these is not a matching pair and why?
Filariasis - *Wuchereria*
Ringworm – *Ascaris*
AIDS - Human Immuno Virus
Malaria - *Plasmodium*
Answer:
The pair that is not a correct match is 'Ringworm - *Ascaris*'.
**Explanation:** Ringworm is a fungal infection, typically caused by *Epidermophyton*, *Trichophyton*, or *Microsporum* species, whereas *Ascaris* is a parasitic roundworm that causes ascariasis. All other pairs listed (*Filariasis - Wuchereria*, *AIDS - Human Immunodeficiency Virus*, *Malaria - Plasmodium*) correctly link a disease to its causative organism.
In simple words: The wrong match is "Ringworm - Ascaris". Ringworm is caused by fungi, but Ascaris is a worm that causes a different disease. All other pairs correctly link the disease to its cause.

🎯 Exam Tip: Carefully check each disease-pathogen pair. Understanding the basic nature of pathogens (bacteria, virus, fungi, parasite) and their associated diseases is crucial.

 

Question 46.
i. In which disease is there an uncontrolled division of cells resulting in formation of tumours? How is this disease detected?
ii. How do interferons help in controlling the disease?
Answer:
i. The disease characterized by the uncontrolled division of cells leading to tumor formation is cancer. This disease is typically detected through methods like biopsy and subsequent histopathological examination of tissue samples.
ii. Interferons contribute to controlling viral diseases by acting as antiviral proteins. They are produced and released by virus-infected cells. These interferons then signal to neighboring uninfected cells, inducing them to become more resistant to further viral infection by synthesizing antiviral proteins.
In simple words: (i) Uncontrolled cell division causing tumors is cancer, detected by biopsy. (ii) Interferons are proteins made by virus-infected cells that warn healthy cells, making them resistant to the virus and stopping its spread.

🎯 Exam Tip: For cancer, know the cellular mechanism (uncontrolled division) and diagnostic methods. For interferons, focus on their role as antiviral proteins in innate immunity.

 

Question 47. What is meant by metastasis?
Answer:
Metastasis refers to the process by which cancerous cells detach from a primary tumor, travel through the bloodstream or lymphatic system, and establish secondary tumors in distant organs or tissues. This translocation of malignant cells from one site to another is a hallmark of advanced cancer.
In simple words: Metastasis is when cancer cells break away from the main tumor and spread to other parts of the body, creating new tumors, usually through blood or lymph.

🎯 Exam Tip: Define metastasis clearly as the spread of cancer cells from a primary site to distant sites, typically via circulatory or lymphatic systems.

 

Question 48. What is rehabilitation?
Answer:
Rehabilitation, particularly for individuals dependent on drugs, is a comprehensive, long-term treatment process. It involves a combination of behavioral training, psychological support, and social therapy aimed at helping patients develop healthier coping mechanisms and responses to triggers that previously led to substance abuse. This includes counseling from family, friends, and medical professionals who educate the patient about the detrimental effects of drugs and encourage complete abstinence in a supportive, non-judgmental environment. Additionally, medical interventions such as vitamin supplementation, nutritional support, and maintaining electrolyte balance and hydration are crucial to restore physical health damaged by drug abuse. For instance, Vitamin C has been noted to help regulate cyclic AMP levels in the brain, which can alleviate withdrawal symptoms.
In simple words: Rehabilitation helps people recover from drug addiction through long-term programs that include counseling, behavioral training, and medical support. The goal is to help them stop using drugs and restore their physical and mental health.

🎯 Exam Tip: Define rehabilitation as a holistic process for recovery from addiction, emphasizing behavioral, psychological, and medical components aimed at sustained abstinence and health restoration.