NDA GK Questions 2026

Melanin absorbs the ultraviolet rays of sunlight and shields the DNA of skin cells from damage. Melanin is made by cells called melanocytes in the lower layer of the epidermis.

This is the order of the taxonomic ranks from the broader group to the narrower one. The full hierarchy set out by Linnaeus and used today runs Kingdom, Phylum (Division in plants), Class, Order, Family, Genus and Species.

Orthophosphoric acid, H 3 PO 4, has three replaceable hydrogen ions, so it is tribasic. The basicity of an acid is the number of hydrogen ions one molecule can give up in water.

Lime water is a solution of calcium hydroxide, Ca(OH) 2, not calcium carbonate.

Liquid pressure at a depth is P = hρg, so a taller column presses harder on the base. In P = hρg, h is the height of the liquid above the point, ρ is the density of the liquid and g is the acceleration due to gravity.

Photosynthesis gives off oxygen, and oxygen is what aerobic respiration needs to release energy from food. In photosynthesis, green plants use sunlight, carbon dioxide and water to make glucose, and release oxygen, which comes from the splitting of water.

Parallels shrink as they move towards the poles, so the 0° parallel, the Equator, is the longest of all. Parallels of latitude are circles drawn parallel to the Equator.

The dogfish is a small shark, and sharks are true fishes of the class Pisces. Pisces are aquatic vertebrates that breathe through gills, swim with fins and usually have scales.

Bile breaks fat into tiny droplets and lipase then splits those droplets into fatty acids and glycerol. Bile is made by the liver, stored in the gall bladder and poured into the duodenum.

Curd contains lactic acid, which reacts with copper and brass to form poisonous salts, so it should not be stored in them.

Weather maps and reports in India give atmospheric pressure in millibars, the same value as hectopascals. Air pressure is the weight of the air column pressing on a unit area.

The Harmattan blows over West Africa towards the Gulf of Guinea, far from the Mediterranean. The Harmattan is a dry, dusty north-easterly trade wind that blows from the Sahara across West Africa between November and March.

A chloride XCl 2 means X has valency 2, and an ionic chloride with a high melting point points to a Group 2 metal such as magnesium.

A solid that does not vaporise stays behind when the solvent is removed, whether the solvent is boiled off or the solid is made to crystallise out.

Because water is densest at 4°C, the bottom of a lake stays liquid and relatively warm while the surface freezes, so aquatic animals survive there.

Bronze is an alloy of copper and tin, usually about 88 parts copper to 12 parts tin. Adding tin makes copper harder, stronger and easier to cast, and bronze also resists corrosion well.

The Kiratarjuniya, a Sanskrit epic poem of the sixth century, was written by Bharavi. The Kiratarjuniya tells, in 18 cantos, a story from the Vana Parva of the Mahabharata: Arjuna performs penance to win divine weapons, and Shiva tests him by appearing as a Kirata, a mountain hunter.

A famine is marked by widespread deaths from starvation and from epidemics, which spread through contaminated water, rotting food and bodies weakened by hunger.

Population ageing is the process by which the share of older people becomes proportionately larger, not lesser, so statement 1 is false, while statement 2 is true.

A hygrometer measures humidity, that is, the amount of water vapour or moisture in the air. The name comes from the Greek "hygros", meaning wet.