General Science Mixed Quiz: Set 125

Only statements 3 and 4 are true; statements 1 and 2 are false. The modern periodic table arranges elements by atomic number.

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.

Animal cells do have vacuoles; they are only small and often temporary, so the statement is wrong. A vacuole is a membrane-bound sac filled with cell sap: water, salts, sugars and waste.

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.

Probiotics include both bacteria and yeasts, and some of them help break down lactose, the sugar in milk. Probiotics are live microorganisms that give a health benefit when eaten in adequate amounts.

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.

A cosmic ray physicist who founded the Physical Research Laboratory at Ahmedabad, he persuaded the government that a poor country needed space technology for communication, weather and education, set up the rocket launching station at Thumba and built the organisation that became the Indian Space Research Organisation.

The endodermis is the innermost layer of the cortex that surrounds the vascular tissue; it is not a part of the vascular bundle itself.

An angiosperm shows double fertilisation: of the two male gametes brought by the pollen tube, one fuses with the egg to give a diploid zygote, and the other fuses with the two polar nuclei of the central cell.

The spring constant is force divided by extension, so its SI unit is newton per metre. Hooke's law says that, within the elastic limit, the restoring force of a spring is proportional to how far it is stretched or compressed: F = −kx.

Hydrogen has three isotopes: protium with one proton and no neutron, deuterium with one neutron, which gives heavy water, and tritium with two neutrons, which is radioactive and is used in fusion research and in luminous dials.

Gypsum (calcium sulphate dihydrate) is not a raw material for glass; it is added to cement to slow down its setting.

The adult human skeleton has 206 bones, of which 80 belong to the axial skeleton, that is the skull, vertebral column and chest, and 126 to the appendicular skeleton of the limbs and girdles.

A perfectly horizontal rope has no upward component of tension, so no finite tension can hold up the 200 N weight with the rope fully straight.

Among the four, microwaves lie farthest towards the long-wavelength end of the electromagnetic spectrum. In order of increasing wavelength the spectrum runs: gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves and radio waves.

Muga silk comes from Antheraea assamensis, reared on Som and Soalu trees of the Brahmaputra valley, and Assam's muga carries a Geographical Indication tag.

This filarial roundworm causes elephantiasis, also called lymphatic filariasis. The adult worms live in the lymphatic vessels and block the flow of lymph, so the legs, arms or genitals swell and the skin thickens, giving the disease its name.

All three statements describe hard water correctly. Statement 1 is correct: temporary hardness comes from dissolved bicarbonates, chiefly calcium bicarbonate (magnesium bicarbonate too).

All three are underground modified stems: the potato is a stem tuber, and onion and garlic are bulbs. A stem can be told from a root by its nodes and buds.

Carrying water and food through the plant is the main job of the stem's vascular tissue, not of the leaf.