General Science Mixed Quiz: Set 124

Rutherford found the nucleus to be positively charged, not neutral. In his gold foil experiment of 1911, Rutherford fired alpha particles at a very thin sheet of gold.

The 2011 FSSAI labelling rules made the list of ingredients, nutrition information and the vegetarian or non-vegetarian mark compulsory, but not medical advice on allergies.

Microbodies are small vesicles bounded by a single membrane, filled with enzymes that carry out particular metabolic reactions. The main microbodies are peroxisomes and glyoxysomes.

Meiosis halves them in the gametes, and fertilisation restores them in the offspring. Each parent makes gametes by meiosis, so a human egg or sperm carries 23 chromosomes instead of 46.

Presbyopia is an age-related loss of near focusing, and it is corrected with bifocal or progressive lenses. With age the ciliary muscles weaken and the eye lens loses its flexibility, so the power of accommodation falls and the near point moves away.

Root hairs are thin outgrowths of the root's epidermal cells that greatly increase the area for absorbing water and minerals.

This is the taxonomic hierarchy for animals, going from the broadest group down to the most specific. Linnaeus built this ladder of ranks, and each rank contains one or more ranks below it.

To just complete a vertical circle, a bob on a string needs a speed of at least √(5gL) at the lowest point, and √(5 × 10 × 0.5) = √25 = 5 m/s. A string can only pull, never push.

Protochordates are marine chordates that have a notochord at some stage but never develop a backbone. The phylum Chordata is split into protochordates and vertebrates.

If pressure is proportional to temperature for a fixed amount of ideal gas, the volume must stay constant, so the process is isochoric.

Biofilms form on almost any moist surface, including implants and food equipment, and they are notoriously hard to kill with antibiotics.

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.

Tendons are made of tightly packed parallel bundles of collagen fibres, which give them great pulling strength. Collagen is the most abundant protein in the human body.

The de Broglie wavelength depends only on momentum, so equal wavelengths mean equal momenta. In 1924 Louis de Broglie proposed that every moving particle has a wave linked to it, with wavelength λ = h/p, where h is Planck's constant and p is the linear momentum.

The cervix is the lower, narrow neck of the uterus, so it belongs to the female reproductive system. The human male reproductive system has a pair of testes that make sperm and the hormone testosterone.

One mole of N₂ weighs 28 g, so half a mole weighs 14 g. A nitrogen molecule is made of two nitrogen atoms, each with an atomic mass of 14 u, so its molecular mass is 28 u and its molar mass is 28 g per mole.

Raman announced in 1928 that light scattered by a transparent medium contains components of changed wavelength, a shift that reveals the energy levels of the scattering molecules, and the Nobel Prize in Physics followed in 1930, making him the first Asian to receive a Nobel in a science.

The word itself means naked seed: the ovules are not enclosed in an ovary, so after fertilisation the seeds lie exposed on the surface of the scales of a cone and no fruit is formed.

A metal more reactive than hydrogen displaces it from a dilute acid, so zinc with dilute sulphuric acid gives zinc sulphate and hydrogen gas, and this is the standard laboratory preparation of the gas; the test is that it burns with a pop.

The stapes, shaped like a stirrup, is the innermost of the three ossicles of the middle ear and is the smallest bone in the human body, measuring only a few millimetres; the smallest muscle of the body, the stapedius, is attached to it.