General Science GK Questions with Answers – Page 46

Khesari dal, botanically Lathyrus sativus and also called grass pea, is a hardy pulse that survives drought and is therefore sometimes mixed with arhar dal or besan.

Argemone mexicana, the prickly poppy known in India as satyanashi, has seeds that look very like mustard seeds, so its oil is a classic adulterant of mustard oil.

A harvested fruit is still a living tissue that keeps respiring, using up its own sugars and acids and giving off heat, carbon dioxide and ethylene.

The sour taste of tamarind comes from tartaric acid, not oxalic acid, so this statement is not correct. Many natural acids give foods their sour taste.

The molar mass of sodium-23 is 23 g, so 46 g is exactly 2 moles, and 2 moles contain twice the Avogadro number of atoms.

In this reaction water accepts a proton (H⁺) from the hydrogen sulphate ion and becomes the hydronium ion, H₃O⁺, and a proton acceptor is a base.

The flying fish is a bony fish with a backbone, gills, scales and fins, so it belongs to the class of fishes; it only glides over the water on its large, wing-like pectoral fins.

Xylem carries water together with the minerals dissolved in it from the roots to the stem and leaves, so blocking it stops both.

Cane sugar, or sucrose, is made of carbon, hydrogen and oxygen joined chemically in a fixed ratio, so it is a compound.

Aluminium oxide reacts with both acids and bases to form salt and water, which is what makes an oxide amphoteric.

Alfalfa, chickpea and clover are legumes, and legumes fix nitrogen. Plants of the legume family (Fabaceae) carry root nodules that house Rhizobium bacteria.

Neither beta nor gamma emission changes the total number of protons and neutrons in a nucleus, so the mass number stays the same.

In facilitated transport, molecules cross the membrane with the help of membrane proteins, while still moving down their concentration gradient.

The American physicist Murray Gell-Mann proposed quarks in 1964 and gave them their name. Gell-Mann, and independently George Zweig, suggested that protons, neutrons and other such particles are built from smaller units.

Spindle fibres attach to the kinetochore, a disc-shaped protein structure on the centromere of each chromosome. During cell division the spindle, made of microtubules, pulls the copies of each chromosome apart.

Heavy water is D₂O: two atoms of deuterium joined to one atom of oxygen. Deuterium is the isotope of hydrogen with one proton and one neutron in its nucleus, so it is about twice as heavy as ordinary hydrogen.

Hydrogen bonds lock the molecules of ice into an open cage, so ice takes up more space than the same mass of liquid water.

An insulator is charged by friction: rubbing transfers electrons from one surface to another, and because electrons cannot move through an insulator, the charge stays where it is as static electricity.

In glass, violet light has the shortest wavelength and the highest refractive index, so it bends the most; dispersion is a result of refraction.

By Newton's second law, F = m × a, so a = F ÷ m = 5 N ÷ 10 kg = 0.5 m/s².