Olive Defence

Biology · NDA

BN07 — Health, Disease & Nutrition

📖 Chapter BN07 · NDA Class 11–12 Level 🎯 NDA Level : High Priority

Health, Disease and Nutrition is a consistently high-scoring chapter in NDA Biology. Questions appear on causative agents of common diseases (especially the vector of malaria, the bacterium in tuberculosis, and the virus in AIDS/hepatitis), vaccine types, types of immunity, and deficiency diseases linked to specific vitamins and minerals. These are direct factual recall questions — systematic revision of the tables in this chapter guarantees marks.

📌 What to expect in NDA (2022–2025 pattern):
(1) Disease → causative agent (bacterium/virus/protozoan/worm) → vector/mode of transmission;
(2) Malaria lifecycle, Plasmodium species and their clinical significance;
(3) AIDS — HIV, T-helper cell destruction, transmission and prevention;
(4) Active vs passive immunity; vaccine types and examples;
(5) Vitamin deficiency diseases — Vitamin, deficiency name, and symptom triad;
(6) Minerals — iron (anaemia), iodine (goitre), calcium (rickets/tetany) linkages.

Topics at a Glance

① Human Diseases

Bacterial, viral, protozoan, helminthic — causative agents & vectors

② Immunity & Vaccines

Innate, acquired (active/passive), vaccine types, antibodies

③ Balanced Diet & Nutrition

Carbohydrates, proteins, fats, vitamins, minerals — sources & deficiency diseases

1. Common Human Diseases

1.1

Disease Classification by Causative Agent

Agent → vector/transmission → prevention: the complete NDA format for every disease

🦠 Bacterial Diseases

Caused by bacteria; mostly treatable with antibiotics

Typhoid: Salmonella typhi; contaminated food/water; rose-red rash on abdomen; Widal test diagnosis
Cholera: Vibrio cholerae; contaminated water; rice-water stools; severe dehydration
Tuberculosis (TB): Mycobacterium tuberculosis; airborne droplets; Koch's bacillus; BCG vaccine prevents it
Plague: Yersinia pestis; vector = rat flea (Xenopsylla cheopis); three forms: bubonic, pneumonic, septicaemic
Pneumonia: Streptococcus pneumoniae (bacterial) or Klebsiella; airborne; lung infection
Tetanus: Clostridium tetani; soil-contaminated wounds; lockjaw (trismus); TT injection prevents
Leprosy: Mycobacterium leprae; affects peripheral nerves + skin; not very contagious; MDT treatment
Diphtheria: Corynebacterium diphtheriae; airborne; grey membrane in throat; DPT vaccine

🔮 Viral Diseases

Caused by viruses; no antibiotics; antivirals or vaccines used

AIDS: HIV (Human Immunodeficiency Virus) — retrovirus; destroys CD4+ T-helper cells; transmitted via blood, sexual contact, breast milk; no cure; ART (antiretroviral therapy)
Hepatitis B: HBV; blood/sexual route; liver inflammation; cirrhosis risk; vaccine available (HBV vaccine)
COVID-19: SARS-CoV-2 coronavirus; respiratory droplets; spike protein targets ACE2 receptor; multiple vaccines developed
Influenza: Influenza virus A/B; airborne; seasonal; annual vaccination needed
Polio: Poliovirus (3 types); faecal-oral route; affects motor neurons; OPV (oral) and IPV vaccines
Rabies: Rhabdovirus; bite of infected animal (dog, bat); affects nervous system; post-exposure vaccination
Dengue: Dengue virus (4 serotypes); vector = Aedes aegypti mosquito; thrombocytopenia (low platelets)
Yellow fever: Flavivirus; vector = Aedes aegypti; jaundice + haemorrhage; vaccine required for travel
Chikungunya: Alphavirus; vector = Aedes aegypti; severe joint pain (chikungunya = "that which bends up")
Smallpox: Variola virus; eradicated globally in 1980 (first disease eradicated by vaccination)

🦡 Protozoan Diseases

Caused by unicellular eukaryotes (protozoans)

Malaria: Plasmodium spp.; vector = female Anopheles mosquito; four species: P. vivax (benign tertian), P. falciparum (malignant tertian; most fatal), P. malariae (quartan), P. ovale; RBC destruction → fever cycles
Amoebiasis (Amoebic dysentery): Entamoeba histolytica; contaminated water/food; bloody diarrhoea; affects large intestine
Kala-azar (Visceral leishmaniasis): Leishmania donovani; vector = sandfly (Phlebotomus); affects spleen, liver, bone marrow
Sleeping sickness: Trypanosoma brucei; vector = tsetse fly; Africa; affects nervous system
Giardiasis: Giardia lamblia; contaminated water; diarrhoea; most common waterborne protozoan disease

🧬 Helminthic (Worm) Diseases

Caused by parasitic worms (helminths)

Elephantiasis (Filariasis): Wuchereria bancrofti; vector = Culex mosquito; lymphatic blockage → massive limb swelling
Ascariasis (Roundworm): Ascaris lumbricoides; faecal-oral; intestinal obstruction; most common worm infection worldwide
Tapeworm (Taeniasis): Taenia solium (pork tapeworm), T. saginata (beef); undercooked meat; intestinal parasitism
Hookworm: Ancylostoma duodenale; soil penetration through skin; anaemia; iron deficiency
Schistosomiasis (Bilharzia): Schistosoma spp.; aquatic snail vector; skin penetration in water
Pinworm: Enterobius vermicularis; faecal-oral; perianal itching; children most affected

Fig. 1 — Malaria transmission cycle. Female Anopheles mosquito injects sporozoites → liver stage (sporozoites → merozoites) → RBC stage (merozoites enter RBCs → rupture → fever; P. vivax: 48h cycles; P. malariae: 72h cycles) → gametocytes ingested by mosquito → sexual cycle in mosquito gut → sporozoites to salivary gland.

📌 Disease → Causative Agent → Vector Table (NDA Direct Recall):

Disease	Causative Agent	Vector / Transmission	Prevention
Malaria	Plasmodium spp.	Female Anopheles mosquito	Nets, DDT, chloroquine, artemisinin
Dengue	Dengue virus (4 types)	Aedes aegypti (day-biting)	Eliminate stagnant water; no specific drug
Chikungunya	Alphavirus	Aedes aegypti	Mosquito control
Yellow fever	Flavivirus	Aedes aegypti	Yellow fever vaccine (mandatory for travel)
Filariasis	Wuchereria bancrofti	Culex mosquito	DEC drug; mosquito control
Plague	Yersinia pestis	Rat flea (Xenopsylla cheopis)	Rat control; antibiotics
Kala-azar	Leishmania donovani	Sandfly (Phlebotomus)	Insecticide spraying; amphotericin B
Sleeping sickness	Trypanosoma brucei	Tsetse fly	Insecticide; suramin drug
Typhoid	Salmonella typhi	Contaminated food/water (faecal-oral)	TAB vaccine; clean water
Cholera	Vibrio cholerae	Contaminated water	ORS; clean water; cholera vaccine
TB	Mycobacterium tuberculosis	Airborne droplets	BCG vaccine; DOTS therapy
AIDS	HIV (retrovirus)	Blood, sexual contact, breast milk	No cure; ART (HAART)

PYQTopic-Wise PYQs — Diseases

Q1. The vector for malaria is:

A. Male Anopheles mosquito
B. Female Aedes mosquito
C. Female Anopheles mosquito
D. Culex mosquito

Answer: C — Female Anopheles mosquito. Only the female Anopheles feeds on blood (males feed on plant juices) and transmits Plasmodium. Aedes aegypti transmits dengue, chikungunya, and yellow fever. Culex transmits filariasis. This is one of the most repeated NDA Biology MCQs.

Q2. Which species of Plasmodium causes the most severe (malignant) form of malaria?

A. P. vivax
B. P. ovale
C. P. malariae
D. P. falciparum

Answer: D — P. falciparum. P. falciparum causes malignant tertian malaria — the most dangerous form, with 48-hour fever cycles. It can cause cerebral malaria (blockage of brain capillaries) and is responsible for most malaria deaths globally. P. vivax causes benign tertian; P. malariae causes quartan (72h cycles); P. ovale is rare.

Q3. HIV destroys which type of cells, leading to AIDS?

A. B-lymphocytes (B cells)
B. Red blood cells
C. CD4+ T-helper cells
D. Platelets

Answer: C — CD4+ T-helper cells. HIV specifically infects and destroys CD4+ T-helper lymphocytes (also called T4 or helper T cells). These cells are central to coordinating the immune response. As their count drops below 200 cells/µL, the immune system fails and opportunistic infections develop — this is AIDS. Normal CD4+ count: 500–1500 cells/µL.

Q4. Widal test is used to diagnose:

A. Malaria
B. Typhoid
C. Cholera
D. Tuberculosis

Answer: B — Typhoid. The Widal test detects antibodies against Salmonella typhi (H and O antigens) in patient's blood serum. It is a serological test. Malaria is diagnosed by blood smear (or RDT kit); TB by Mantoux test (PPD skin test) or sputum microscopy; Cholera by stool culture. Widal = typhoid is a classic NDA question.

TRICKY🧐 Disease Traps

⚠️ "Dengue and malaria are both transmitted by Anopheles mosquitoes." True or False?

False. Malaria is transmitted by female Anopheles. Dengue, chikungunya, yellow fever, and Zika are transmitted by Aedes aegypti (and A. albopictus). Culex transmits filariasis and Japanese encephalitis. A simple memory rule: Anopheles = malaria only; Aedes = dengue/chikungunya/yellow fever; Culex = filariasis. NDA frequently exploits this confusion.

⚠️ "Cholera is caused by a virus." True or False?

False. Cholera is caused by the bacterium Vibrio cholerae (gram-negative, comma-shaped bacterium). It produces cholera toxin (CT) which causes massive secretion of water and electrolytes from gut epithelium → rice-water stools → severe dehydration. Treatment = ORS (Oral Rehydration Solution) + antibiotics (doxycycline). Being bacterial, it responds to antibiotics unlike viral diseases.

2. Immunity & Vaccines

2.1

Types of Immunity

Innate vs Acquired; Active vs Passive — all four types with examples are NDA-tested

Fig. 2 — Immunity classification. Innate immunity is non-specific (no memory, present from birth). Acquired immunity is specific to antigens, has memory, and is mediated by B and T lymphocytes. Acquired immunity is either Active (body makes its own antibodies) or Passive (pre-formed antibodies given externally).

▶ Active Immunity

Body produces its own antibodies in response to antigen
Long-lasting; develops immunological memory
Natural active: infection by pathogen (e.g. chickenpox infection → lifelong immunity)
Artificial active: vaccination (e.g. MMR vaccine → body produces antibodies against measles, mumps, rubella)
Slower to develop (days to weeks) but durable (months to lifetime)

▶ Passive Immunity

Body receives ready-made antibodies from external source
Immediate protection; short-lived (no memory formed)
Natural passive: antibodies from mother to foetus (via placenta — IgG) or to infant (via breast milk — IgA)
Artificial passive: antiserum injection (e.g. anti-rabies antiserum, anti-snake venom, anti-tetanus serum = ATS)
Lasts only weeks to months

📌 Vaccines — NDA Key Facts:
Live attenuated vaccines: weakened live pathogen — BCG (TB), OPV (Polio), MMR, Varicella
Killed/Inactivated vaccines: killed pathogen — IPV (Salk polio), Influenza (injectable), Hepatitis A, Rabies
Toxoid vaccines: inactivated toxin — DT (Diphtheria-Tetanus), TT (Tetanus Toxoid)
Subunit vaccines: specific antigen only — Hepatitis B vaccine (HBsAg), HPV vaccine
mRNA vaccines: COVID-19 vaccines (Pfizer/BioNTech, Moderna) — first approved mRNA vaccines in history
India's BCG vaccine (1948): oldest vaccination programme; mandatory for newborns in India.

PYQTopic-Wise PYQs — Immunity

Q5. Antibodies received by a newborn through mother's milk (colostrum) represent which type of immunity?

A. Natural active
B. Artificial active
C. Natural passive
D. Artificial passive

Answer: C — Natural passive immunity. When a mother passes antibodies (IgA) to her newborn through colostrum (first milk), the baby does not produce these antibodies itself — they are received passively. This is natural because it occurs naturally (not through medical injection). Artificial passive = antiserum injection. Natural active = getting the actual infection. Artificial active = vaccination.

Q6. BCG vaccine is used to prevent:

A. Cholera
B. Typhoid
C. Tuberculosis
D. Tetanus

Answer: C — Tuberculosis. BCG (Bacillus Calmette-Guérin) is a live attenuated vaccine made from weakened Mycobacterium bovis (bovine TB bacterium). It is given to newborns in India (and many countries) at birth to prevent TB. BCG vaccine is especially effective against severe forms of childhood TB (miliary TB and TB meningitis).

TRICKY🧐 Immunity Traps

⚠️ "Vaccination provides passive immunity." True or False?

False. Vaccination provides active immunity (artificial active). A vaccine introduces antigens (dead, weakened, or parts of a pathogen) into the body. The body then actively produces its own antibodies and memory cells. This takes time (days to weeks) but provides long-lasting protection. Passive immunity is when pre-formed antibodies are given directly (e.g. antiserum injection) — immediate but short-lived. The key distinction: active = you make the antibodies; passive = you receive them.

3. Balanced Diet & Nutrition

3.1

Macronutrients — Carbohydrates, Proteins & Fats

Energy values, sources, functions, and daily requirements — all NDA-tested basics

Nutrient	Energy (kcal/g)	Sources	Key Functions	Storage
Carbohydrates	4 kcal/g	Rice, wheat, potato, sugar, fruits	Primary energy source; brain runs almost exclusively on glucose	Glycogen in liver & muscles
Proteins	4 kcal/g	Meat, fish, eggs, milk, dal, soybean	Growth, repair, enzymes, antibodies, hormones (insulin), haemoglobin	No specific store; used/synthesised continuously
Fats (Lipids)	9 kcal/g	Butter, ghee, oil, nuts, cheese	Energy reserve; fat-soluble vitamin (A,D,E,K) absorption; insulation; cell membrane	Adipose tissue

🧠 Energy Memory: Fat = 9 kcal/g (Fats are F-ine and Nine); Carbs = 4 kcal/g; Protein = 4 kcal/g. Alcohol = 7 kcal/g. Fat gives more than double the energy per gram compared to carbs or protein — that's why fat is the best energy store.

3.2

Vitamins — Types, Sources & Deficiency Diseases

Fat-soluble (A,D,E,K) vs Water-soluble (B complex, C) — deficiency name + disease = NDA format

Vitamin A (Retinol)

Fat-soluble | Source: Carrot, fish liver oil, egg yolk, green leafy veg (beta-carotene)

Function: Vision (rhodopsin in rod cells); skin health; immunity
Deficiency: Night blindness (nyctalopia); Xerophthalmia (dry eyes); Bitot's spots on cornea
Excess (toxicity): Hypervitaminosis A; liver damage; birth defects

Vitamin B Complex (8 vitamins)

Water-soluble | Source: Cereals, meat, eggs, legumes, green vegetables

B1 (Thiamine): deficiency = Beriberi (peripheral neuropathy; wet/dry forms)
B2 (Riboflavin): deficiency = Ariboflavinosis (cracked lips, angular stomatitis)
B3 (Niacin): deficiency = Pellagra (3 Ds: Dermatitis, Diarrhoea, Dementia)
B9 (Folic acid): deficiency = Megaloblastic anaemia; neural tube defects in foetus
B12 (Cobalamin): deficiency = Pernicious anaemia; requires intrinsic factor for absorption

Vitamin C (Ascorbic Acid)

Water-soluble | Source: Citrus fruits (lemon, orange), amla, guava, bell peppers

Function: Collagen synthesis; antioxidant; iron absorption; wound healing; immune function
Deficiency: Scurvy — bleeding gums, loose teeth, poor wound healing, sub-periosteal haemorrhage
Amla (Indian gooseberry) has the highest vitamin C content of any fruit
Destroyed by cooking (heat-labile)

Vitamin D (Calciferol)

Fat-soluble | Source: Sunlight (skin synthesis), fish liver oil, egg yolk, fortified milk

Function: Calcium and phosphorus absorption; bone mineralisation; immune regulation
Deficiency in children: Rickets (bowing of legs, soft bones)
Deficiency in adults: Osteomalacia (soft bones, bone pain)
"Sunshine vitamin" — only vitamin made by body from sunlight (UVB radiation)

Vitamin E (Tocopherol)

Fat-soluble | Source: Vegetable oils, nuts, seeds, green leafy vegetables

Function: Antioxidant (protects cell membranes from oxidative damage); fertility; immune function
Deficiency: Haemolytic anaemia (in premature infants); infertility; peripheral neuropathy
Rare deficiency in adults with adequate diet

Vitamin K (Phylloquinone)

Fat-soluble | Source: Green leafy vegetables (spinach, kale), liver; synthesised by gut bacteria

Function: Blood clotting (activates clotting factors II, VII, IX, X); bone metabolism
Deficiency: Bleeding disorders (haemorrhagic disease); prolonged clotting time
Newborns given Vitamin K injection at birth (gut bacteria not yet established)
Warfarin (anticoagulant) works by blocking Vitamin K action

3.3

Minerals — Key Elements, Sources & Deficiency Diseases

Iron, iodine, calcium, and fluoride linkages are the most tested NDA mineral MCQs

Mineral	Key Sources	Function	Deficiency Disease
Iron (Fe)	Spinach, liver, red meat, jaggery, fortified cereals	Component of haemoglobin (O₂ transport); myoglobin; enzymes	Iron-deficiency anaemia (microcytic, hypochromic) — fatigue, pallor
Iodine (I)	Iodised salt, seafood, seaweed	Component of thyroid hormones (T3, T4)	Goitre (thyroid enlargement); Cretinism (if deficient in pregnancy/childhood); Hypothyroidism
Calcium (Ca)	Milk, dairy, ragi, sesame seeds, leafy vegetables	Bone/teeth structure; muscle contraction; nerve transmission; blood clotting	Rickets (children, with Vit D deficiency); Osteoporosis (adults); Tetany (low Ca → muscle spasms)
Phosphorus (P)	Meat, fish, dairy, nuts, legumes	ATP energy; bones and teeth (calcium phosphate); DNA/RNA backbone	Rickets (with Ca deficiency); bone fragility
Fluoride (F)	Fluoridated water, tea, seafood	Strengthens tooth enamel; prevents dental caries	Deficiency: Dental caries (tooth decay); Excess: Fluorosis (mottled teeth, skeletal fluorosis)
Zinc (Zn)	Meat, oysters, nuts, legumes, whole grains	Wound healing; immune function; enzyme cofactor; growth	Growth retardation; poor wound healing; impaired immunity; taste/smell loss
Sodium (Na)	Table salt, processed foods	Fluid balance; nerve impulse; muscle contraction	Hyponatraemia (muscle cramps, confusion); Excess: hypertension

📌 NDA Deficiency Disease Quick Reference (Most Tested):
Night blindness = Vitamin A | Scurvy = Vitamin C | Rickets = Vitamin D + Ca | Beriberi = Vitamin B1
Pellagra = Vitamin B3 (Niacin) = 3 Ds (Dermatitis, Diarrhoea, Dementia) | Anaemia = Iron or B12 or Folic acid
Goitre = Iodine | Bleeding disorder = Vitamin K | Osteoporosis = Calcium | Dental caries = Fluoride deficiency

PYQTopic-Wise PYQs — Nutrition & Deficiency Diseases

Q7. Night blindness is caused by deficiency of:

A. Vitamin C
B. Vitamin D
C. Vitamin A
D. Vitamin K

Answer: C — Vitamin A. Vitamin A (retinol) is essential for synthesising rhodopsin, the light-sensitive pigment in rod cells of the retina. Rod cells function in low-light conditions. Vitamin A deficiency → insufficient rhodopsin → inability to see in dim light (night blindness / nyctalopia). Severe deficiency also causes xerophthalmia and Bitot's spots on cornea.

Q8. Scurvy is caused by the deficiency of:

A. Vitamin A
B. Vitamin B12
C. Vitamin C
D. Vitamin D

Answer: C — Vitamin C (Ascorbic acid). Vitamin C is required for collagen synthesis (the structural protein of connective tissue). Deficiency → poor collagen → bleeding gums, loose teeth, poor wound healing, haemorrhages under skin (purpura). Scurvy was historically prevalent in sailors on long voyages (no fresh fruits → no Vitamin C). Citrus fruits (lemon, orange) and amla prevent/cure scurvy.

Q9. Goitre is caused by deficiency of which mineral?

A. Iron
B. Calcium
C. Zinc
D. Iodine

Answer: D — Iodine. Iodine is essential for synthesising thyroid hormones (T3 = triiodothyronine and T4 = thyroxine). Deficiency → thyroid cannot make hormones → pituitary releases more TSH → thyroid gland enlarges (compensatory hypertrophy) → Goitre. Iodine deficiency during pregnancy → Cretinism in child (stunted growth + mental retardation). Prevention: Iodised salt.

Q10. Pellagra is the deficiency disease caused by lack of:

A. Vitamin B1 (Thiamine)
B. Vitamin B3 (Niacin)
C. Vitamin B12 (Cobalamin)
D. Vitamin B9 (Folic acid)

Answer: B — Vitamin B3 (Niacin). Pellagra is characterised by the "3 Ds": Dermatitis (photosensitive skin rash, especially on sun-exposed areas), Diarrhoea, and Dementia (and death in severe cases = 4th D). Common in populations dependent on corn (maize) diet without lime treatment (corn lacks bioavailable niacin). Beriberi = B1; Pernicious anaemia = B12; Neural tube defects = Folic acid.

TRICKY🧐 Nutrition Traps

⚠️ "Rickets is caused by calcium deficiency alone." True or False?

Partially false — it's usually a combined deficiency of Vitamin D AND calcium. Vitamin D is essential for absorption of calcium from the gut. Without Vitamin D, even if dietary calcium is adequate, it cannot be absorbed → bones remain soft (rickets in children; osteomalacia in adults). In practice, NDA questions frame rickets as "Vitamin D deficiency" disease because Vitamin D is the primary deficiency causing impaired calcium absorption. Pure calcium deficiency without Vitamin D deficiency is less common.

⚠️ "All vitamins are obtained only from diet." True or False?

False. Two vitamins can be made by the body itself: Vitamin D (synthesised in skin from 7-dehydrocholesterol under UVB sunlight) and Vitamin K (partly synthesised by gut bacteria — E. coli and other intestinal flora). Vitamin B12 and biotin are also partially produced by gut bacteria but dietary intake is still needed. Vitamin C cannot be synthesised by humans (we lack the enzyme L-gulonolactone oxidase) — making it a true essential vitamin.

📄 Quick-Reference Fact Sheet — BN07

🦠 Disease → Agent (Bacterial)

Typhoid → Salmonella typhi (Widal test)
Cholera → Vibrio cholerae (rice-water stools)
TB → Mycobacterium tuberculosis (BCG vaccine)
Plague → Yersinia pestis (rat flea vector)
Tetanus → Clostridium tetani (lockjaw; TT injection)
Leprosy → Mycobacterium leprae (peripheral nerves)

🔮 Disease → Agent (Viral & Protozoan)

AIDS → HIV (destroys CD4+ T-helper cells)
Dengue → Dengue virus; vector = Aedes aegypti
Yellow fever → Flavivirus; Aedes aegypti
Malaria → Plasmodium; female Anopheles
Filariasis → Wuchereria bancrofti; Culex
Kala-azar → Leishmania donovani; sandfly
Amoebiasis → Entamoeba histolytica; food/water

🔴 Malaria Species

P. falciparum: malignant tertian (most fatal; 48h)
P. vivax: benign tertian (48h; hypnozoites)
P. malariae: quartan (72h fever cycles)
P. ovale: ovale malaria (rare; like vivax)
Vector: female Anopheles mosquito only
Haemozoin → jaundice; RBC lysis → anaemia

💊 Immunity Types

Innate: non-specific, no memory, from birth
Acquired: specific, has memory, via B/T cells
Active natural: recovering from infection
Active artificial: vaccination
Passive natural: mother's antibodies (IgA via breast milk)
Passive artificial: antiserum injection (ATS, anti-rabies)
Vaccination = active immunity (NOT passive)

🌿 Vitamin Deficiency Diseases

Vit A → Night blindness; Xerophthalmia
Vit B1 (Thiamine) → Beriberi
Vit B3 (Niacin) → Pellagra (3 Ds)
Vit B12 → Pernicious anaemia
Vit C → Scurvy (bleeding gums, loose teeth)
Vit D → Rickets (child); Osteomalacia (adult)
Vit K → Bleeding disorder; prolonged clotting
Folic acid (B9) → Megaloblastic anaemia; neural tube defects

🧸 Mineral Deficiency Diseases

Iron → Iron-deficiency anaemia (microcytic)
Iodine → Goitre; Cretinism (in child if mother deficient)
Calcium + Vit D → Rickets / Osteoporosis / Tetany
Fluoride deficiency → Dental caries (tooth decay)
Fluoride excess → Fluorosis (mottled teeth, skeletal)
Fat gives 9 kcal/g; Carbs & Protein = 4 kcal/g
Fat-soluble vitamins: A, D, E, K; Water-soluble: B, C

⚡ Quick Revision Booster — BN07

🦠 Bacterial Disease Shortcuts

Typhoid = Salmonella; Widal test
Cholera = Vibrio; rice-water stools; ORS
TB = Mycobacterium; BCG vaccine; DOTS
Tetanus = lockjaw; TT injection
Plague = rat flea (Xenopsylla)

🔸 Mosquito → Disease

Anopheles (female) → Malaria only
Aedes aegypti → Dengue, Chikungunya, Yellow fever
Culex → Filariasis, Japanese encephalitis
Malaria: P. falciparum = most fatal
HIV destroys CD4+ T-helper cells

💊 Immunity Shortcuts

Vaccination = Active artificial immunity
Breast milk antibodies = Passive natural
Antiserum injection = Passive artificial
Infection recovery = Active natural
BCG = TB; OPV/IPV = Polio; MMR = Measles/Mumps/Rubella

🌿 Vitamin Deficiency Shortcuts

Night blindness = Vit A
Scurvy = Vit C (bleeding gums)
Rickets = Vit D (+ Calcium)
Beriberi = Vit B1; Pellagra = Vit B3 (3 Ds)
Pernicious anaemia = Vit B12

🧸 Mineral Shortcuts

Iodine → Goitre / Cretinism
Iron → Anaemia (microcytic)
Fluoride deficiency → Dental caries
Fluoride excess → Fluorosis
Ca + Vit D → Rickets (child), Osteomalacia (adult)

📌 NDA Classic Traps

Malaria vector = female Anopheles (NOT Aedes)
Vaccination = active (NOT passive)
Rickets = Vit D + Ca (not Ca alone)
Vit D made by sunlight; Vit K by gut bacteria
Cholera = bacteria (NOT virus)

📝 Mock Tests 🎯 Subject Quizzes ✈️ Telegram