LGS 2026: Top 100 General Science Facts — SSLC Level Revision

SSLC-level science facts for the LGS exam on April 26, 2026. Expect 8-10 science questions. Pure memorisation — no calculations needed.

Vitamins — The Most Asked Topic

Vitamin	Chemical Name	Source	Deficiency Disease
Vitamin A	Retinol	Carrot, milk, fish oil	Night blindness, Xerophthalmia
Vitamin B1	Thiamine	Cereals, pulses	Beriberi
Vitamin B2	Riboflavin	Milk, eggs, green vegetables	Cheilosis (cracked lips)
Vitamin B3	Niacin	Meat, groundnut	Pellagra
Vitamin B5	Pantothenic acid	Meat, eggs, milk	Burning feet syndrome
Vitamin B6	Pyridoxine	Meat, fish, banana	Anaemia
Vitamin B7	Biotin	Eggs, nuts	Dermatitis
Vitamin B9	Folic Acid	Green leafy vegetables	Megaloblastic anaemia
Vitamin B12	Cyanocobalamin	Meat, fish, eggs	Pernicious anaemia
Vitamin C	Ascorbic Acid	Citrus fruits, amla	Scurvy
Vitamin D	Calciferol	Sunlight, fish oil	Rickets (children), Osteomalacia (adults)
Vitamin E	Tocopherol	Vegetable oils, nuts	Sterility
Vitamin K	Phylloquinone	Green leafy vegetables	Delayed blood clotting

Key Vitamin Facts	Answer
Fat-soluble vitamins	A, D, E, K
Water-soluble vitamins	B complex, C
Vitamin synthesised by sunlight	Vitamin D
Anti-sterility vitamin	Vitamin E
Anti-haemorrhagic vitamin	Vitamin K

Common Diseases and Causes

Disease	Caused By	Type
Malaria	Plasmodium (mosquito-borne)	Protozoan
Dengue	Dengue virus (Aedes mosquito)	Viral
Chikungunya	Chikungunya virus (Aedes mosquito)	Viral
Typhoid	Salmonella typhi	Bacterial
Cholera	Vibrio cholerae	Bacterial
Tuberculosis (TB)	Mycobacterium tuberculosis	Bacterial
Tetanus	Clostridium tetani	Bacterial
Rabies	Rabies virus (dog/animal bite)	Viral
COVID-19	SARS-CoV-2	Viral
AIDS	HIV (Human Immunodeficiency Virus)	Viral
Ringworm	Fungi (Dermatophytes)	Fungal
Athlete’s foot	Fungi	Fungal
Diabetes	Insulin deficiency	Metabolic
Anaemia	Iron deficiency	Nutritional
Goitre	Iodine deficiency	Nutritional
Kwashiorkor	Protein deficiency	Nutritional
Marasmus	Protein-calorie deficiency	Nutritional

Disease Vector	Answer
Malaria mosquito	Female Anopheles
Dengue mosquito	Aedes aegypti
Plague	Rat flea
Sleeping sickness	Tsetse fly
Kala-azar	Sand fly

SI Units

Quantity	SI Unit	Symbol
Length	Metre	m
Mass	Kilogram	kg
Time	Second	s
Temperature	Kelvin	K
Electric current	Ampere	A
Luminous intensity	Candela	cd
Amount of substance	Mole	mol

Other Important Units	Answer
Force	Newton (N)
Energy/Work	Joule (J)
Power	Watt (W)
Pressure	Pascal (Pa)
Electric charge	Coulomb (C)
Voltage	Volt (V)
Resistance	Ohm
Frequency	Hertz (Hz)
Speed of light	3 x 10^8 m/s
Acceleration due to gravity	9.8 m/s^2

Human Body Basics

Organ/System	Key Fact
Largest organ	Skin
Smallest bone	Stapes (ear)
Largest bone	Femur (thigh)
Total bones in adult	206
Total bones in baby	~300
Total muscles	~600
Blood groups	A, B, AB, O
Universal donor	O negative
Universal recipient	AB positive
Normal body temperature	37 degrees C (98.6 degrees F)
Normal BP	120/80 mmHg
Pumping organ	Heart
Number of chambers in heart	4
Largest gland	Liver
Largest endocrine gland	Thyroid
Master gland	Pituitary gland
Largest cell in human body	Ovum (egg cell)
Smallest cell in human body	Sperm (male) / RBC (excluding reproductive)
RBC lifespan	120 days
WBC lifespan	13-20 days
Total chromosomes	46 (23 pairs)
Blood volume in adult	~5 litres

Scientists and Their Discoveries/Inventions

Scientist	Discovery/Invention
Isaac Newton	Laws of Motion, Gravity
Albert Einstein	Theory of Relativity (E=mc^2)
Thomas Edison	Practical electric light bulb, phonograph
Alexander Graham Bell	Telephone
Wright Brothers	Aeroplane
Marie Curie	Radioactivity (Radium, Polonium)
Alexander Fleming	Penicillin (first antibiotic)
Louis Pasteur	Pasteurisation; Rabies vaccine
Edward Jenner	Smallpox vaccine
Charles Darwin	Theory of Evolution (Natural Selection)
Gregor Mendel	Laws of Heredity (Genetics)
William Harvey	Blood circulation
J.C. Bose	Crescograph (plant growth measurement)
C.V. Raman	Raman Effect (Nobel Prize 1930)
Homi Bhabha	Father of Indian Nuclear Programme
Vikram Sarabhai	Father of Indian Space Programme
A.P.J. Abdul Kalam	Missile Man of India
Srinivasa Ramanujan	Mathematical genius
James Watt	Improved steam engine
Michael Faraday	Electromagnetic induction
Galileo Galilei	Telescope (astronomical use); heliocentric proof
Johannes Gutenberg	Printing press

Physics Basics

Concept	Key Fact
Speed formula	Distance / Time
Newton’s 1st Law	Object at rest stays at rest (Inertia)
Newton’s 2nd Law	Force = Mass x Acceleration
Newton’s 3rd Law	Every action has equal and opposite reaction
Gravity	Pulls objects towards Earth’s centre
Sound travels fastest in	Solids
Sound cannot travel through	Vacuum
Light travels fastest in	Vacuum
Speed of sound in air	~343 m/s
Reflection	Bouncing of light
Refraction	Bending of light
Rainbow colours (VIBGYOR)	Violet, Indigo, Blue, Green, Yellow, Orange, Red
Convex lens	Converges light (magnifying glass)
Concave lens	Diverges light (used in myopia correction)
Myopia (short-sightedness)	Concave lens corrects
Hypermetropia (long-sightedness)	Convex lens corrects

Chemistry Basics

Concept	Key Fact
pH of pure water	7 (neutral)
Acidic pH	Below 7
Basic/Alkaline pH	Above 7
Smallest particle of element	Atom
Smallest particle of compound	Molecule
Chemical formula of water	H2O
Chemical formula of salt	NaCl
Chemical formula of carbon dioxide	CO2
Rusting	Iron + Oxygen + Moisture = Iron oxide
Photosynthesis	CO2 + Water + Sunlight = Glucose + O2
Hardest natural substance	Diamond
Most abundant gas in atmosphere	Nitrogen (78%)
Second most abundant	Oxygen (21%)
Ozone layer	Protects from UV rays; in stratosphere
Ozone depleting substance	CFCs (chlorofluorocarbons)
Noble/Inert gases	Helium, Neon, Argon, Krypton, Xenon, Radon
Lightest element	Hydrogen
Lightest metal	Lithium
Most abundant element in Earth’s crust	Oxygen
Most abundant metal in Earth’s crust	Aluminium

Biology Basics

Concept	Key Fact
Basic unit of life	Cell
Cell discovered by	Robert Hooke (1665)
Powerhouse of the cell	Mitochondria
Control centre of cell	Nucleus
Plant cell wall made of	Cellulose
Photosynthesis pigment	Chlorophyll (green)
Photosynthesis occurs in	Chloroplast
Respiration gas taken in	Oxygen
Respiration gas given out	Carbon dioxide
DNA full form	Deoxyribonucleic Acid
RNA full form	Ribonucleic Acid
Father of Genetics	Gregor Mendel
Father of Taxonomy	Carolus Linnaeus
Study of birds	Ornithology
Study of insects	Entomology
Study of fungi	Mycology
Study of snakes	Ophiology

Space and Environment

Fact	Answer
Nearest planet to Sun	Mercury
Largest planet	Jupiter
Smallest planet	Mercury
Red Planet	Mars
Morning/Evening Star	Venus
Planet with rings	Saturn
Earth’s natural satellite	Moon
Planet nearest to Earth	Venus
Time for Earth to orbit Sun	365.25 days
Time for Earth to rotate on axis	24 hours
Rotation causes	Day and Night
Revolution causes	Seasons
Greenhouse gases	CO2, Methane, Water vapour, N2O
Global warming caused by	Increase in greenhouse gases
Renewable energy sources	Solar, Wind, Hydro, Biomass
Non-renewable energy sources	Coal, Petroleum, Natural gas

Important Days Related to Science

Day	Date
National Science Day	28 February (Raman Effect)
World Environment Day	5 June
World Health Day	7 April
World AIDS Day	1 December
Earth Day	22 April
Ozone Day	16 September
National Technology Day	11 May
World Water Day	22 March

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Tip: Vitamins-diseases table is the single highest-yield science topic for LGS. If you memorise nothing else, memorise that table. Scientists-inventions is the second most asked.