RRB Group D GK Questions 2026

The carrot stores food in its primary root, which is broad at the top and tapers steadily to a point, and that shape is described as conical.

The potato is an underground stem tuber, the swollen tip of an underground branch, and the proof is in its morphology: it bears nodes, the depressions called eyes, and each eye carries an axillary bud that can sprout into a new shoot.

Halophytes are plants of saline soils, chiefly the mangroves of tidal creeks and deltas such as Rhizophora and Avicennia, and their morphology is shaped by that habitat: they bear pneumatophores, negatively geotropic breathing roots that rise out of the waterlogged mud, along with stilt and prop roots for support and…

The Sirhind Canal is taken from the Sutlej at Ropar, now Rupnagar, and is one of the oldest canal systems of Punjab, irrigating a large tract of the Malwa region and parts of Haryana.

The Agra Canal leaves the right bank of the Yamuna at the Okhla barrage to the south of Delhi and carries water to the districts of Agra and Mathura in Uttar Pradesh, with branches reaching parts of Haryana and Rajasthan.

The scheme was launched in 2015 to bring the scattered irrigation programmes under one roof, and its components include Har Khet Ko Pani, which aims to extend assured irrigation to every field, Per Drop More Crop, which promotes drip and sprinkler systems, the Accelerated Irrigation Benefit Programme for incomplete major…

In drip irrigation water is carried through pipes and released slowly, drop by drop, at the root zone of each plant through emitters, so losses to evaporation, runoff and deep percolation are the lowest of all methods and fertiliser can be delivered with the water.

Tank irrigation is characteristic of the peninsula, especially Telangana, Andhra Pradesh, Tamil Nadu and Karnataka, for three reasons: the hard crystalline rock of the plateau makes the digging of wells difficult and holds little groundwater, the rivers of the peninsula are seasonal and cannot feed perennial canals, and the uneven…

Groundwater drawn through wells and tube wells irrigates the largest part of the net irrigated area of India, and its share has risen steadily since the Green Revolution because a tube well gives water on demand, close to the field and without waiting for a canal turn.

The Buckingham Canal is a salt water navigation canal dug in the nineteenth century along the eastern coast, linking the lagoons and backwaters between Vijayawada in Andhra Pradesh and Chennai in Tamil Nadu, and it was used to carry goods and to relieve famine by moving grain.

The Grand Anicut, known in Tamil as Kallanai, was thrown across the Cauvery by the Chola king Karikala in about the second century to spread the river's water over the delta, and it still serves the canals of the Cauvery delta in Tamil Nadu.

The Upper Ganga Canal was opened in 1854 and is taken from the Ganga at Haridwar, from where it runs down the Ganga–Yamuna Doab and irrigates the districts of western Uttar Pradesh; the engineer associated with its construction is Proby Cautley.

The Harike barrage stands in Punjab at the point where the Beas joins the Sutlej, and the Indira Gandhi Canal begins there as the Rajasthan Feeder before continuing as the main canal into Rajasthan.

Begun in 1958 as the Rajasthan Canal and renamed in 1984, it is the longest canal in India; its feeder and main canal together run for about six hundred and fifty kilometres and carry water from the Punjab rivers into the Thar desert of western Rajasthan.

The skin is the largest organ of the human body by both surface area and weight, and it is the organ of touch; it is made of an outer epidermis and an inner dermis that carries blood vessels, nerve endings, hair follicles, sweat glands and sebaceous glands.

Rhodopsin, the pigment of the rod cells that makes vision in dim light possible, is formed from a derivative of vitamin A, so when the vitamin is lacking the rods cannot work properly and the person is unable to see in faint light, a condition called night blindness or nyctalopia…

The Eustachian tube, also called the auditory tube, runs from the cavity of the middle ear to the nasopharynx, the upper part of the throat behind the nose, and its function is to keep the air pressure on the inner side of the eardrum equal to the pressure outside.

The blind spot, also called the optic disc, is the small area of the retina from which the fibres of the optic nerve pass out of the eyeball; it has neither rods nor cones, so an image falling on it is not registered and we do not notice the gap…

In myopia the eyeball is too long or the lens too strongly curved, so light from a distant object is brought to a focus in front of the retina and the distant object appears blurred.

Rhodopsin, also called visual purple, is the pigment of the rod cells; it is extremely sensitive to light, which is why rods allow us to see in dim light, though only in shades of black and white.