14 public questions tagged with this topic.
AIDS is caused by HIV, which destroys CD4+ T-lls, leading to immune system failure. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Human Health and Disease, Topic: Immunity, diseases and health maintenance.
Malaria, caused by Plasmodium species, is characterized by recurring fever and chills due to the release of haemozoin toxin. This follows from latest NCERT 2026-27 principle explaining the concept clearly for NEET students in simple steps as per rationalized syllabus.
Ref: NCERT Biology Textbook - Latest Edition for Academic Session 2026-27 (Zoology section, Rationalized Textbook for Class XI and XII), Chapter: Biology - Zoology portion (Latest NCERT Textbooks for Academic Session 2026-27 - Rationalized Edition for Class XI and XII), Topic: Structural organization, physiology, human health and related concepts as per latest syllabus.
Gonorrhea is caused by the bacterium *Neisseria gonorrhoeae*, whereas HIV/AIDS, genital herpes, and Hepatitis B are caused by viruses. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function.
Glycopeptide antibiotics exhibit true bactericidal killing activity rather than simple growth arrest, a distinction critical for treating severe Gram-positive infections. Vancomycin functions by recognizing and binding with high affinity to the D-alanyl-D-alanine dipeptide terminus of the peptidoglycan precursor lipid II that is exposed on the outer face of the cytoplasmic membrane after flipping from the cytoplasm. This binding creates a large steric cap that prevents transglycosylases from polymerizing the alternating N-acetylglucosamine and N-acetylmuramic acid glycan chain and simultaneously blocks transpeptidases, the penicillin-binding proteins, from forming peptide cross-links between stems. Without cross-linking, the nascent peptidoglycan mesh in Gram-positive organisms with 20-80 nm thick wall remains mechanically weak and cannot withstand internal turgor pressures of 20 atmospheres, leading to activation of autolysins and osmotic lysis. Tetracycline, erythromycin and clindamycin bind reversibly to bacterial ribosomes, pausing translation temporarily and causing bacteriostatic arrest where cells resume growth after drug removal, explaining clinical preference for vancomycin in MRSA bacteremia and endocarditis where rapid killing is desired.
Ref: Madigan et al., Brock Biology of Microorganisms, 16th ed., Chapter 5: Glycopeptide Antibiotics and Cell Wall Inhibition.
HIV is not transmitted through casual contact such as hugging, shaking hands, or sharing food.
Ref: NCERT Class 12 Biology Chapter 7: Human Health and Disease Cancer - Causes Types Treatment Metastasis
Amoebiasis is caused by the protozoan Entamoeba histolytica, which infects the human intestine.
Ref: NCERT Class 12 Biology Chapter 7: Human Health and Disease Common Diseases - Protozoan - Malaria Amoebiasis
Malaria is caused by Plasmodium, a protozoan, and not by bacteria.
Ref: NCERT Class 12 Biology Chapter 7: Human Health and Disease Common Diseases - Protozoan - Malaria Amoebiasis
Rabies is a zoonotic disease, meaning it is transmitted from animals to humans, usually through bites from infected animals.
Ref: NCERT Class 12 Biology Chapter 7: Human Health and Disease Common Diseases - Bacterial - Typhoid Pneumonia
Tuberculosis is a bacterial disease caused by Mycobacterium tuberculosis.
Ref: NCERT Class 12 Biology Chapter 7: Human Health and Disease Common Diseases - Bacterial - Typhoid Pneumonia
Cholera is caused by Vibrio cholerae, a bacterium that spreads through contaminated water and food.
Ref: NCERT Class 12 Biology Chapter 7: Human Health and Disease Common Diseases - Bacterial - Typhoid Pneumonia
Cholera toxin catalyzes ADP-ribosylation of Gαs, locking the subunit in its GTP-bound active form by inhibiting GTPase activity. Persistent activation of adenylyl cyclase produces massive elevations of cAMP in intestinal epithelial cells, leading to continuous opening of chloride channels and the characteristic watery diarrhea of cholera. Careful
Ref: NCERT Biology Class 11–12 Alberts et al Molecular Biology of the Cell Lodish et al, Molecular Cell Biology Cooper & Hausman, The Cell Abbas et al., Cellular and Molecular Immunology (for immunology sections)
