General Science Mixed Quiz: Set 154

Petroleum ether is a solvent and petroleum jelly is spread on metal surfaces as a protective coating, while the uses given for petroleum wax and white spirit have been swapped around.

Palaeontology is the study of fossils, the preserved remains or traces of organisms of past geological ages, and it supplies the evidence on which the history of life and the theory of evolution rest.

Statement 1 has both genomes wrong, while statement 2 is a correct fact. Adenoviruses carry a double-stranded DNA genome.

The lead-acid cell has a spongy lead negative plate and a lead dioxide positive plate dipped in dilute sulphuric acid, and as the cell discharges both plates turn to lead sulphate while the acid becomes weaker, which is why its state of charge can be judged from the specific gravity…

A water molecule has two hydrogen atoms of atomic mass one and one oxygen atom of atomic mass sixteen, so the masses are two and sixteen, which is a ratio of one to eight; this fixed ratio in every sample of water, whatever its source, is the classic illustration of…

At a fixed speed v, centripetal acceleration equals v²/r, so a larger radius gives a smaller acceleration. An object moving in a circle at constant speed is still accelerating, because its direction keeps changing.

Gustatory receptors are the receptors of taste, and they lie in the taste buds of the tongue, which sit mostly on small projections called papillae; they are stimulated by chemicals dissolved in saliva and send impulses to the brain.

DNA copies itself from loosened chromatin, and chromatin condenses into chromosomes before division, but prokaryotes divide differently from eukaryotes. In a non-dividing eukaryotic cell, DNA lies in the nucleus as a loose network called chromatin.

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.

High pressure pushes the gas molecules close together and low temperature slows them down, so the attractive forces can hold them as a liquid.

When a wire is stretched its volume stays the same, so the length must grow in the same ratio as the cross-sectional area shrinks.

Crown gall is caused by the bacterium Agrobacterium tumefaciens, which enters through a wound near the base, or crown, of the stem and makes the plant grow rough tumour-like swellings there.

Flint glass contains lead oxide, which gives it a high refractive index and clarity, so it is used for lenses and prisms of optical instruments.

In 1905 Einstein explained the photoelectric effect by treating light as made of packets of energy, later called photons, and he received the 1921 Nobel Prize in Physics for this work.

The stapes, also called the stirrup because of its shape, lies in the middle ear and is the smallest bone in the human body; it passes the vibration received from the eardrum on to the oval window of the inner ear.

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.

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.

Carborundum, or silicon carbide (SiC), is one of the hardest substances known, so it can grind, cut and polish other materials, which is what an abrasive must do.

The three semicircular canals of the inner ear are set at right angles to one another and are filled with fluid; movement of the head moves the fluid, which stimulates the receptors and tells the brain about the position and motion of the head, so that balance or equilibrium is…

The banyan's horizontal branches grow so long and heavy that they send down thick aerial roots which reach the soil, thicken into pillars and carry the weight of the branch; these are called prop or pillar roots.