Vitamins & Minerals

Vitamins & Minerals

Vitamins are organic micronutrients required in small amounts for normal metabolism. They function primarily as coenzymes or their precursors, and cannot be synthesized in adequate amounts by the body.

Fat-Soluble Vitamins (A, D, E, K)

Stored in liver and adipose tissue. Risk of toxicity with excess intake. Absorbed with dietary fats.

  • Vitamin A (Retinol): Night vision (rhodopsin), cell differentiation, immune function. Deficiency: Night blindness, xerophthalmia. Toxicity: Teratogenicity.
  • Vitamin D (Calciferol): Calcium & phosphorus homeostasis. Synthesized in skin (UV light). Activated in liver → kidney (1,25-dihydroxycholecalciferol = calcitriol). Deficiency: Rickets (children), Osteomalacia (adults).
  • Vitamin E (Tocopherol): Antioxidant; protects cell membranes from oxidation. Deficiency: Hemolytic anemia, neuropathy.
  • Vitamin K (Phylloquinone): Required for γ-carboxylation of clotting factors (II, VII, IX, X) and proteins C and S. Warfarin antagonizes Vit K. Deficiency: Bleeding tendency.

Water-Soluble Vitamins (B-complex & C)

Not stored; excess excreted in urine (except B12). Deficiency develops more rapidly.

  • B1 (Thiamine) → TPP: Oxidative decarboxylation (PDH, α-KGDH). Deficiency: Beriberi (wet=cardiac, dry=neurological), Wernicke-Korsakoff (alcoholics).
  • B2 (Riboflavin) → FAD/FMN: Electron carriers in oxidative phosphorylation.
  • B3 (Niacin) → NAD+/NADP+: Most important coenzyme. Deficiency: Pellagra (3Ds: Dermatitis, Diarrhea, Dementia). Tryptophan is precursor.
  • B5 (Pantothenic acid) → CoA: Fatty acid metabolism.
  • B6 (Pyridoxine) → PLP: Transamination, decarboxylation. Deficiency: Peripheral neuropathy, sideroblastic anemia.
  • B7 (Biotin): Carboxylation reactions (ACC, Pyruvate carboxylase). Avidin in raw egg whites binds biotin → deficiency.
  • B9 (Folate → THF): One-carbon transfers; nucleotide synthesis. Deficiency: Megaloblastic anemia, Neural tube defects (NTDs).
  • B12 (Cobalamin): Requires intrinsic factor (IF) for absorption. Cofactor for methionine synthase & methylmalonyl-CoA mutase. Deficiency: Megaloblastic anemia + subacute combined degeneration of spinal cord.
  • Vitamin C (Ascorbic acid): Antioxidant; collagen synthesis (hydroxylation of Pro & Lys). Deficiency: Scurvy (bleeding gums, perifollicular hemorrhages, poor wound healing).

Essential Minerals

  • Iron: Component of heme (Hb, Mb, cytochromes). Deficiency: Microcytic hypochromic anemia. Absorbed as Fe²⁺; haem-iron better absorbed.
  • Calcium: Bone/teeth, muscle contraction, blood clotting, nerve function.
  • Iodine: Thyroid hormone synthesis. Deficiency: Goiter, Cretinism.
  • Zinc: Metalloenzyme cofactor (carbonic anhydrase, carboxypeptidase). Wound healing.
  • Selenium: Antioxidant; part of glutathione peroxidase.

Quiz - Exam Preparation Strategy

When studying Quiz for your final board exams, it is critical to focus on the core concepts and fundamental formulas. Relying strictly on NCERT textbook solutions and practicing previous year questions (PYQs) is the proven methodology for scoring high marks. Avoid rote memorization and instead focus on the logical application of the theories presented in this chapter.

⚠️ Common Mistakes to Avoid

❓ Frequently Asked Questions

How can I quickly memorize the concepts of Quiz?

The most effective way is to create short, handwritten revision notes and continuously test your knowledge using our interactive Mock Tests. Spaced repetition and active recall are much better than passive reading.

What type of questions are most commonly asked from Quiz?

Board exams tend to favor conceptual application questions and direct formula-based derivations from the NCERT syllabus. Ensure you have solved every single exercise in the official textbook.

Is reading the NCERT book enough for this chapter?

Yes, the NCERT textbook is the absolute gold standard for board exams. However, to improve your speed and accuracy during the actual exam, you must supplement your reading by solving timed mock tests and objective questions.