Defence GK Questions 2026

During the war of 1971 Indian missile boats struck Karachi harbour in an action that sank enemy vessels and set the oil installations on fire, and 4 December is kept as Navy Day in memory of it.

On this day in 1949 Field Marshal K. M. Cariappa took over as the first Indian Commander in Chief of the Indian Army, and the day is marked with a parade and the presentation of gallantry awards.

The lateral meristem, better known as the cambium, lies as a ring along the length of the stem and root and divides to add new xylem on its inner side and new phloem on its outer side, so the stem grows thicker year after year; this is secondary growth, and…

Blood is classed as a connective tissue because its cells lie in a matrix, and because that matrix, the plasma, is liquid it is called a fluid connective tissue; the red cells, white cells and platelets float in it and it connects the organs of the body by carrying gases…

The muscle of the heart shows light and dark bands under the microscope, so it is striated, yet it is not under the control of the will and it contracts rhythmically without rest for the whole of life, so it is involuntary; this unusual combination is exactly why it is…

A neuron carries a long process called an axon, which in a human being may run from the base of the spine to the toe, so a single nerve cell can be about a metre long; this length lets one cell carry an impulse over a great distance without any…

Xylem is a complex permanent tissue of tracheids, vessels, xylem parenchyma and xylem fibres; the vessels and tracheids are dead, hollow and joined end to end, which makes them ideal pipes for carrying water and minerals from the root to the leaves in one direction.

A tendon is made of dense white fibrous connective tissue with great tensile strength and almost no elasticity, so when a muscle contracts the whole pull is transmitted to the bone without being lost in stretching.

Matthias Schleiden, a botanist, concluded that all plants are made of cells, and Theodor Schwann, a zoologist, reached the same conclusion for animals; together their statement became the cell theory.

A lysosome is a membrane-bound sac of powerful digestive enzymes that breaks down worn-out organelles and any foreign particle the cell takes in; if the cell is damaged or starving, the sacs burst and the same enzymes digest the cell itself, which is why the name suicide bag is used.

Both carry a small circular DNA of their own and their own 70S ribosomes, so they make a part of their protein themselves and divide independently of the cell; this semi-autonomous nature is the main evidence for the view that they descend from free-living bacteria engulfed by an early cell.

In 1665 he cut a thin slice of cork, examined it under a microscope of his own making and saw rows of empty boxes, which he named cells after the small rooms of a monastery; the drawing and description appeared in his book Micrographia.

From that date the manufacture, import, stocking, distribution, sale and use of a listed set of single-use plastic articles became an offence across the country; the list covers earbuds with plastic sticks, plastic sticks for balloons and flags, candy and ice-cream sticks, thermocol used for decoration, plates, cups, glasses, cutlery…

The mission was launched on the 145th birth anniversary of Mahatma Gandhi, whose insistence on sanitation the campaign invokes, and it runs in two wings, one for urban areas and one for rural areas.

In pyrolysis the waste is heated to a high temperature in a closed chamber from which air is kept out, so the material does not burn but breaks into a liquid oil, a solid char and a combustible gas, all of which can be used as fuel or feedstock.

Vermicomposting uses earthworms, which swallow organic waste, grind it in their gizzard and pass it out as casts that are rich in nitrogen, phosphorus and potassium, so the product is a finer and more nutritious manure than ordinary compost and is ready sooner.

The Basel Convention was adopted in 1989 to stop rich countries from shipping toxic and hazardous waste to poorer countries for cheap disposal, and it requires the prior informed consent of the receiving country before any such consignment moves.

Under this idea a producer, importer or brand owner stays answerable for its product after the consumer has finished with it, and must arrange to collect back and recycle an agreed quantity of packaging or equipment; the plastic waste, e-waste and battery waste rules all run on it.

In biomethanation, anaerobic bacteria break down organic matter inside a closed digester where no oxygen is present, and the gas they release is mainly methane, which is what makes biogas burn with a clean blue flame and gives it its fuel value.

Microplastics are plastic particles under five millimetres across, whether they were manufactured that small, as in cosmetic microbeads and synthetic textile fibres, or were formed when larger plastic articles weathered and broke up in sunlight and waves.