General Science Mixed Quiz: Set 210

A liquid has no shape of its own, so it must be measured inside a vessel that expands at the same time.

Sublimation is the change from solid to vapour without passing through the liquid stage. It happens when particles of the solid gain enough energy to escape straight into the gas phase, and the reverse change, gas to solid, is called deposition.

The rod becomes negative because it gains electrons from the wool. When two materials are rubbed together, only electrons move, because they are the loosely held outer particles of atoms.

A gamma ray is a photon of energy with no mass and no charge, so emitting it leaves the count of protons and neutrons unchanged.

Tincture of iodine is made from iodine, potassium iodide, alcohol and water; acetone is not one of its ingredients. A tincture is a solution in alcohol.

A p-type semiconductor is made by adding a small amount of a trivalent impurity, such as boron, aluminium, gallium or indium, to pure silicon or germanium.

They are the proteins around which DNA winds to form chromatin in the nucleus of eukaryotic cells. Histones are small basic proteins, rich in the positively charged amino acids lysine and arginine, which attract the negatively charged phosphate groups of DNA.

Nichrome has a high resistivity and does not oxidise easily when red hot, so it is the standard heating element.

Liver cells turn the toxic ammonia released from the breakdown of amino acids into urea through the ornithine cycle, also called the urea cycle.

Unsaturated hydrocarbons have a high carbon content and burn with a yellow, sooty flame, while saturated ones usually burn with a clean blue flame.

Both statements describe how cancer starts and how it spreads, and both are correct. Cancer is uncontrolled division of cells.

Nylon 6 is made from a single monomer, caprolactam, whose ring opens on heating and joins up into long polyamide chains.

The Calvin cycle fixes carbon dioxide into sugar without needing light directly, so it forms the light-independent (dark) reactions. Photosynthesis happens in two stages inside the chloroplast.

All rose plants of one kind belong to a single species, the basic unit of classification. A species is a group of individuals that are alike in their main features and can interbreed in nature to produce fertile offspring.

The power of a lens measures how strongly it bends light, and +2.5 D has the largest magnitude among the four options.

Flatworms, the phylum Platyhelminthes, have an incomplete digestive system with just one opening, so the same mouth takes the food in and throws the waste out.

Natural rubber is a polymer of isoprene, a hydrocarbon, and contains no sugar units at all. Natural rubber is cis-1,4-polyisoprene, obtained from the latex of the rubber tree Hevea brasiliensis; its monomer isoprene (2-methyl-1,3-butadiene) has the formula C5H8.

This statement is false, because yeast is one of the few fungi that are unicellular. In Whittaker's five-kingdom system, fungi form a separate kingdom.

Nereis, the clamworm, is an annelid, and annelids are bilaterally symmetrical: only one plane divides the body into identical left and right halves.

Agaricus is a mushroom, a fungus that feeds on dead and decaying organic matter, which is the saprophytic mode of nutrition.