General Science GK Questions with Answers – Page 26

Fungi have no chlorophyll, so they cannot make their own food by photosynthesis.

Sulphur dissolves completely in carbon disulphide, so the two form a true solution, and a solution is a homogeneous mixture.

Light, small and dry pollen is a feature of wind-pollinated plants, not of plants that depend on insects. Insect-pollinated (entomophilous) flowers have to attract a visitor and then make the pollen travel on its body.

The 2015 film 'The Man Who Knew Infinity' tells the life of the Indian mathematician Srinivasa Ramanujan and is based on Robert Kanigel's 1991 biography of the same name.

Denisovans were an archaic group of humans, close relatives of the Neanderthals, first identified in 2010 from a finger bone found in Denisova Cave in the Altai Mountains of Siberia.

B cells and T cells are lymphocytes, the white blood cells of the adaptive immune system that recognise and fight specific bacteria, viruses and other pathogens.

Ammonium sulphide is an unstable, foul-smelling compound that breaks down to release ammonia and toxic hydrogen sulphide, so it is not used as a fertiliser.

For an astronomical telescope in normal adjustment the magnifying power equals the focal length of the objective divided by that of the eyepiece, so the eyepiece focal length is 50 ÷ 25 = 2 cm.

Vegetables and fruits supply most of the vitamins and minerals in a vegetarian diet, which is why they are called protective foods.

Silver bromide is the light-sensitive compound coated on black and white photographic film and paper, because light breaks it down into tiny grains of silver metal.

Speed tells only how fast a body moves, while velocity also tells the direction of motion, and a quantity with both magnitude and direction is a vector.

A hypertonic solution has a higher solute concentration than the cell sap, so water leaves the cells by osmosis and the protoplast shrinks away from the cell wall.

Magnesium oxide melts at about 2,850 °C, far higher than the other three, because its small Mg2+ and O2− ions carry double charges and hold each other with a very strong ionic lattice.

That is false: in a physical change the molecules stay the same, and only their arrangement, state or shape alters.

Cardiac muscle is a muscular tissue, not a connective tissue; it is the striated, branched, involuntary muscle that makes up the wall of the heart and contracts rhythmically for life.

Genuine currency notes carry security features printed with fluorescent inks that glow only under ultraviolet light, so a UV lamp quickly exposes a fake.

When magnesium burns, magnesium loses electrons and is oxidised, while oxygen gains them and is reduced, so oxidation and reduction happen together.

A light year is the distance that light travels through a vacuum in one year, so despite the word year it measures length, not time.

A freely pivoted magnetic needle turns to line up with any magnetic field around it, so its deflection shows that a field is present and which way it points.

Without oxygen, yeast carries out alcoholic fermentation, breaking glucose into ethanol and carbon dioxide and gaining a little ATP. Glucose is first split into two molecules of pyruvate by glycolysis, which yields a net gain of two ATP.