Chapter 8: Diseases

Select the correct answer:

1. What the patient feels when he goes to the doctor is:

A) disease

B) illness

C) acute infection

D) diagnosis

Answer: B) illness

Explanation: Illness refers to the subjective feeling of being unwell, including symptoms like pain, nausea, or fatigue, which prompt a patient to seek medical attention. Disease is the objective, diagnosable pathological condition.

2. Bone fracture is a/an:

A) acute disease

B) chronic disease

C) infectious disease

D) zoonotic disease

Answer: A) acute disease (Note: A bone fracture is technically an injury or trauma, not a disease. However, in medical classification, it is considered an acute condition because it has a sudden onset and a relatively short course. It is not infectious or chronic.)

3. Virus and bacteria are examples of:

A) vectors

B) pathogens

C) disease

D) illness

Answer: B) pathogens

Explanation: Pathogens are microorganisms that cause disease. Viruses and bacteria are the most common types of pathogens. Vectors are organisms that transmit pathogens (e.g., mosquitoes).

4. Mosquito is the deadliest animals on earth because:

A) It has poison glands

B) It can cause infection

C) It can spread pathogens

D) It sucks blood

Answer: C) It can spread pathogens

Explanation: Mosquitoes are considered the deadliest animals because they act as vectors, transmitting deadly diseases like malaria, dengue, yellow fever, and Zika virus to millions of people each year, causing significant mortality.

5. The non-infectious diseases that run in the family are:

A) physiological disorders

B) genetic disorders

C) autoimmune disorders

D) nutritional disorders

Answer: B) genetic disorders

Explanation: Genetic disorders are caused by abnormalities in an individual's DNA (mutations) and are inherited from parents. Examples include cystic fibrosis, sickle cell anemia, and hemophilia. They are non-infectious.

6. COVID-19 is a/an:

A) acute bacterial infection

B) chronic bacterial infection

C) acute viral infection

D) chronic viral infection

Answer: C) acute viral infection

Explanation: COVID-19 is caused by the SARS-CoV-2 virus. It is an acute viral infection because it has a sudden onset, and the initial infection typically lasts for a short period (though it can have long-term effects, often called "long COVID").

7. COVID-19 spread as global pandemic was reduced after:

A) lockdowns

B) social distancing

C) sanitization

D) vaccination

Answer: D) vaccination

Explanation: While lockdowns, social distancing, and sanitization helped slow the spread, the global reduction in the severity and spread of the pandemic was primarily achieved through the widespread administration of effective vaccines.

8. HIV positive person can stay up to 10 years in stage:

A) 1

B) 2

C) 3

D) 4

Answer: B) 2 (Note: The stages of HIV infection vary, but clinically, a person can remain asymptomatic (Stage 1 or 2) for an average of 10 years without treatment. Stage 3 is symptomatic HIV, and Stage 4 is AIDS.)

9. According to the International Diabetes Federation, in 2022, 26.7% of adults in Pakistan are affected by diabetes. This number is alarmingly high and is also increasing with each passing year. We can:

A) do nothing about it

B) make prayers to stop it

C) make life style changes to prevent it

D) use vaccination to cure it

Answer: C) make life style changes to prevent it

Explanation: Type 2 diabetes is largely preventable through lifestyle modifications such as a healthy diet, regular exercise, and

weight management. There is no vaccine to cure diabetes.

10. The rapid creation of abnormal cells that grow beyond their usual boundaries and spread to other organs is due to:

A) AIDS

B) diabetes

C) cancer

D) COVID-19

Answer: C) cancer

Explanation: Cancer is characterized by the uncontrolled growth and division of abnormal cells that can invade nearby tissues and spread (metastasize) to other parts of the body.

11. Which of the following CORRECTLY matches the antibiotic with its source?

Answer: D) Tetracycline - Bacteria (Note: Tetracycline is produced by Streptomyces bacteria. Streptomycin is also from bacteria (Streptomyces), Penicillin is from fungi (Penicillium), and Cephalosporin is from fungi (Cephalosporium).)

12. First antibiotic discovered by Alexander Fleming in 1928 was:

A) Streptomycin

B) Cephalosporin

C) Penicillin

D) Tetracycline

Answer: C) Penicillin

Explanation: Alexander Fleming discovered penicillin in 1928 from the fungus Penicillium notatum. It revolutionized medicine by providing a cure for bacterial infections.

13. Drug resistant typhoid is lethal due to:

A) highly toxic bacteria

B) antibiotics resistance

C) severe complications

D) allergic reactions

Answer: B) antibiotics resistance

Explanation: Drug-resistant typhoid is caused by bacteria (Salmonella typhi) that have developed resistance to multiple antibiotics. This makes the infection much harder to treat, increasing the risk of severe complications and death.

14. If all pathogenic bacteria develop antibiotic resistance then health issues will increase regarding:

A) all infectious diseases

B) non infectious diseases

C) viral diseases

D) bacterial diseases

Answer: D) bacterial diseases

Explanation: Antibiotics are only effective against bacterial infections. If all pathogenic bacteria become resistant, we would lose the ability to treat bacterial diseases effectively.

15. Membrane disruption antibiotics can be grouped as:

A) bacteriostatic

B) bactericidal

C) pesticide

D) antiviral

Answer: B) bactericidal

Explanation: Antibiotics that disrupt the bacterial cell membrane cause the cell to lyse and die. Therefore, they are classified as bactericidal (kills bacteria). Bacteriostatic antibiotics inhibit growth without killing.

1. What are zoonotic diseases?

Answer: Zoonotic diseases (zoonoses) are infectious diseases that can be transmitted from animals to humans. They can be caused by bacteria, viruses, parasites, or fungi. Examples include rabies (from dogs), malaria (from mosquitoes), COVID-19 (likely from bats), and salmonellosis (from poultry). Transmission can occur through direct contact, bites, or vectors.

2. Enlist types of pathogens with examples.

Answer:

Bacteria: Single-celled prokaryotes. Example: Salmonella typhi (typhoid). Viruses: Acellular infectious agents. Example: SARS-CoV-2 (COVID-19). Fungi: Eukaryotic organisms. Example: Candida albicans (candidiasis). Protozoa: Single-celled eukaryotes. Example: Plasmodium (malaria). Helminths: Parasitic worms. Example: Ascaris lumbricoides (roundworm). Prions: Misfolded proteins. Example: Creutzfeldt-Jakob disease.

3. What are different types of non-infectious diseases?

Answer: Non-infectious diseases are not caused by pathogens and cannot be transmitted from person to person. Types include:

Genetic Disorders: Caused by mutations (e.g., sickle cell anemia). Nutritional Disorders: Caused by deficiencies or excesses (e.g., scurvy, obesity). Metabolic Disorders: Caused by malfunction of metabolism (e.g., diabetes). Autoimmune Disorders: Immune system attacks self (e.g., rheumatoid arthritis). Degenerative Disorders: Progressive deterioration (e.g., Alzheimer's). Cancer: Uncontrolled cell growth.

4. What are the effects of diabetes on human body?

Answer: Diabetes affects the body by:

Cardiovascular: Increases risk of heart disease, stroke, and hypertension.

Nervous System: Causes neuropathy (nerve damage), leading to tingling, pain, and loss of sensation. Kidneys: Causes nephropathy, leading to kidney failure. Eyes: Causes retinopathy, leading to vision loss and blindness. Feet: Poor circulation and nerve damage can lead to ulcers and amputation. Skin: Increases risk of infections and slow healing.

5. What are different types of diabetes?

Answer:

Type 1 Diabetes: Autoimmune destruction of insulin-producing beta cells. Requires insulin injections. Type 2 Diabetes: Insulin resistance and relative insulin deficiency. Managed with lifestyle changes and medication. Gestational Diabetes: Develops during pregnancy. Pre-diabetes: Blood sugar is higher than normal but not high enough for diabetes diagnosis.

6. How diabetes can be prevented and managed?

Answer: Diabetes can be prevented and managed by:

Healthy Diet: Low sugar, low saturated fat, high fiber. Regular Exercise: At least 30 minutes daily. Weight Management: Maintaining a healthy weight. Medication: Insulin or oral hypoglycemic drugs. Monitoring: Regular blood sugar checks. Education: Understanding the disease and self-care.

7. How cancer develops and spreads in the body?

Answer: Cancer develops due to genetic mutations that cause uncontrolled cell division. These cells form a mass (tumor). Malignant tumors can invade nearby tissues and spread (metastasize) through the bloodstream or lymphatic system to other parts of the body, forming secondary tumors.

8. How cancer can be treated?

Answer: Cancer treatment depends on the type and stage. Options include:

Surgery: Removal of the tumor. Chemotherapy: Drugs to kill cancer cells. Radiation Therapy: High-energy rays to destroy cancer cells. Immunotherapy: Boosting the immune system to fight cancer. Targeted Therapy: Drugs that target specific cancer cell molecules. Hormone Therapy: For hormone-sensitive cancers.

9. Which systems of the body are affected by COVID-19?

Answer: COVID-19 primarily affects the respiratory system (lungs), causing pneumonia and acute respiratory distress syndrome (ARDS). It can also affect:

Cardiovascular System: Heart damage, myocarditis. Nervous System: Loss of smell/taste, strokes. Digestive System: Nausea, diarrhea. Kidneys: Acute kidney injury.

10. What are the clinical stages of AIDS?

Answer: The clinical stages of HIV/AIDS are:

1. Acute HIV Infection: Flu-like symptoms 2-4 weeks after infection.

2. Clinical Latency (Asymptomatic): No symptoms, but virus is active. Can last 10+ years.

3. Symptomatic HIV: Persistent symptoms like fever, weight loss, infections.

4. AIDS: CD4 count drops below 200. Opportunistic infections and cancers occur.

11. What are the sources of antibiotics?

Answer: Antibiotics are derived from:

Fungi: Penicillin (from Penicillium), Cephalosporin (from Cephalosporium). Bacteria: Streptomycin, Tetracycline (from Streptomyces). Semi-synthetic: Chemically modified natural antibiotics.

12. What are different ways in which antibiotics act on bacteria?

Answer: Antibiotics act by:

1. Inhibiting Cell Wall Synthesis: Penicillins, Cephalosporins.

2. Inhibiting Protein Synthesis: Tetracyclines, Macrolides.

3. Inhibiting Nucleic Acid Synthesis: Fluoroquinolones, Rifampicin.

4. Disrupting Cell Membrane: Polymyxins.

5. Inhibiting Metabolic Pathways: Sulfonamides.

13. Which factors contribute to the resistance of antibiotics and how it can be prevented?

Answer: Factors contributing to antibiotic resistance:

Overuse/Misuse: Taking antibiotics for viral infections. Incomplete Courses: Not finishing prescribed antibiotics. Agricultural Use: Using antibiotics in livestock. Genetic Mutations: Bacteria naturally mutate.

Prevention:

Only use antibiotics when prescribed. Complete the full course. Avoid sharing antibiotics. Practice good hygiene. Use antibiotics judiciously in agriculture.

14. Write the differences between:

a. Disease and illness

Answer: Disease is an objective, diagnosable pathological condition. Illness is the subjective feeling of being unwell.

b. Infectious and non-infectious diseases

Answer: Infectious diseases are caused by pathogens and are transmissible. Non-infectious diseases are not caused by pathogens and are not transmissible.

c. Vector and pathogen

Answer: A vector is an organism that transmits a pathogen. A pathogen is the microorganism that causes disease.

d. Acute and chronic diseases

Answer: Acute diseases have a sudden onset and short duration. Chronic diseases are long-lasting.

1. Describe infectious and non-infectious diseases and their types with examples.

Answer: Infectious Diseases: Caused by pathogens and can be transmitted from one person to another.

Bacterial: Cholera, tuberculosis, typhoid. Viral: COVID-19, AIDS, influenza. Fungal: Ringworm, candidiasis. Protozoan: Malaria, amoebic dysentery. Helminthic: Ascariasis, schistosomiasis.

Non-Infectious Diseases: Not caused by pathogens and are not transmissible.

Genetic: Sickle cell anemia, cystic fibrosis. Nutritional: Scurvy, rickets. Metabolic: Diabetes, thyroid disorders. Autoimmune: Rheumatoid arthritis, lupus. Degenerative: Alzheimer's, osteoporosis. Cancer: Lung cancer, breast cancer.

In summary, infectious diseases are transmissible, while non-infectious diseases are not.

2. Describe diabetes and its subtypes. Explain the effects of diabetes on the human body.

Answer: Diabetes: A metabolic disorder characterized by high blood sugar levels due to defects in insulin secretion, insulin action, or both.

Subtypes:

Type 1: Autoimmune destruction of beta cells. Type 2: Insulin resistance and relative insulin deficiency. Gestational: Develops during pregnancy.

Effects on the Body:

Cardiovascular: Heart disease, stroke. Nervous: Neuropathy. Renal: Nephropathy, kidney failure. Ocular: Retinopathy, blindness. Peripheral: Poor wound healing, amputation.

In summary, diabetes affects multiple organ systems and requires careful management.

3. Discuss cancer and its effects on the human body.

Answer: Cancer: A group of diseases characterized by uncontrolled cell growth and division.

Effects on the Body:

Local: Tumor growth, pain, bleeding. Systemic: Weight loss, fatigue, anemia. Organ Dysfunction: Depending on the site (e.g., lung cancer causes breathing difficulty).

Metastasis: Spread to other organs, causing secondary tumors. Immune Suppression: Increased risk of infections.

In summary, cancer can cause widespread damage and is a leading cause of death worldwide.

4. Explain Covid-19 and its harmful effects on the human body.

Answer: COVID-19: An infectious disease caused by the SARS-CoV-2 virus.

Harmful Effects:

Respiratory: Pneumonia, ARDS, difficulty breathing. Cardiovascular: Myocarditis, blood clots. Neurological: Loss of smell/taste, strokes. Systemic: Fever, fatigue, muscle pain. Long COVID: Persistent symptoms for months.

In summary, COVID-19 can cause severe multi-system complications.

5. Discuss that HIV compromises the immune system and over times leads to development Acquired Immune Deficiency Syndrome (AIDS).

Answer: HIV (Human Immunodeficiency Virus) attacks and destroys CD4+ helper T cells, which are crucial for coordinating the immune response. Over time, the number of CD4+ cells declines, weakening the immune system. When the CD4 count drops below 200 cells/mm³, the person is diagnosed with AIDS (Acquired Immune Deficiency Syndrome). At this stage, the body becomes vulnerable

to opportunistic infections and cancers that a healthy immune system would normally defeat. Thus, HIV compromises the immune system, leading to AIDS.

6. Explain plant diseases commonly present in Pakistan, in terms of their effect on plant health and yield and their treatment.

Answer: Common plant diseases in Pakistan:

Wheat Rust: Fungal disease causing orange/yellow pustules on leaves, reducing yield. Treatment: Fungicides, resistant varieties. Cotton Leaf Curl Virus (CLCuV): Viral disease transmitted by whiteflies, causing leaf curling and stunted growth. Treatment: Vector control, resistant varieties. Rice Blast: Fungal disease causing diamond-shaped lesions on leaves. Treatment: Fungicides, resistant varieties. Bacterial Blight of Rice: Bacterial disease causing wilting. Treatment: Resistant varieties, sanitation. These diseases significantly reduce crop yields and affect food security.

7. Narrate the discovery of first antibiotic.

Answer: The first antibiotic, penicillin, was discovered by Alexander Fleming in 1928. While working at St. Mary's Hospital in London, Fleming noticed that a petri dish containing Staphylococcus bacteria had been contaminated by a mold (Penicillium notatum). Around the mold, the bacteria had been destroyed. Fleming isolated the substance responsible, which he named penicillin. This discovery revolutionized medicine by providing a cure for bacterial infections. Florey and Chain later purified penicillin for mass production.

8. Discuss antibiotics in detail.

Answer: Antibiotics are drugs used to treat bacterial infections. They work by killing bacteria (bactericidal) or inhibiting their growth (bacteriostatic). They target structures or processes unique to bacteria, such as cell wall synthesis, protein synthesis, and nucleic acid synthesis. Antibiotics are derived from fungi, bacteria, or synthesized chemically. They are ineffective against viruses. Misuse leads to antibiotic resistance. Examples include penicillin, tetracycline, and streptomycin.

9. Describe antibiotic resistance and its effects.

Answer: Antibiotic resistance is the ability of bacteria to survive and grow in the presence of antibiotics that would normally kill them. It occurs through genetic mutations or acquisition of resistance genes from other bacteria. Effects include:

Treatment Failure: Infections become harder to treat. Increased Mortality: Severe infections become life-threatening. Higher Costs: Longer hospital stays and expensive alternative drugs. Global Health Threat: Spread of resistant strains (e.g., MRSA, drug-resistant TB). Prevention includes judicious antibiotic use, completing courses, and infection control.