encyclopedia

When the sunlight enters our atmosphere, its waves collide with gas molecules. The longer wavelengths, like red and yellow, pass straight through it. But the shorter wavelengths, like blue, collide with the gas molecules and scatter in all directions. Some of the blue light still makes it through directly, but the rest is reflected back […]

The expiry dates of medicines are manufacturers’ guarantee of the full potency and safety of drugs. If the medicine is used within its shelf life, maximal efficacy and safety of the drug is ensured. It reflects the ability of the drug in curing the disease or reducing symptoms. However, expired medication may not adequately treat

Tonic water glows and will fluoresce under UV rays because of quinine in it. Quinine is one of the most important alkaloids found in the cinchona bark, among many others. It has some rare earth compounds known as phosphors that glow when they hit certain wavelengths of the UV light. Phosphors in the quinine absorb

A bird’s feathers grow from the epidermis of the bird’s skin and can be divided into ‘semiplumes’, ‘filoplume’, ‘bristle’ and ‘powder feathers’. Given their impeccable daily routine, birds maintain their feathers by preening, dust bathing and even bathing in the water. When birds preen themselves with their beaks, they pick up oil by rubbing the

Milk appears white because it reflects all light wavelengths. If it were to do absorb all light wavelengths and reflect nothing back, then it would appear black. Milk is primarily water, which absorbs the light wavelengths; but it also has other components: fat, protein, lactose, minerals and vitamins. The fat and protein molecules in the

Animals have developed adaptability to blend in their surroundings. This is necessary so that they may remain hidden from their hunters or even from their prey that they are hunting. This is called ‘camouflage’. They can camouflage by merging themselves with their backgrounds or by having patterns on their bodies that break up their outline,

Wolf-like dogs lived in the wild in earlier ages where they slept out in the open, without much warmth or safety or comfort, unlike their pampered ‘pet’ friends now. They lived in packs and travelled constantly looking for food and shelter. For resting, they would perform the circling behaviour, smoothen out the uneven surface to

While walking on their webs, spiders do not come in contact with the strands of their webs all at once. Their legs are covered with hundreds of little hair and they move lightly over their webs with just the tip of their hair of their legs. Additionally, a spider uses its claws to grip each

According to research, sunlight plays a vital role in affecting our general health and happiness. The correlation between light and mood is unquestionable. Our body produces serotonin, a neurotransmitter, that regulates our appetite, moods and memory, and melatonin, a hormone that promotes sleep. As the sun rises and hits upon our optic nerves, a gland

Flies need soft and moist areas to breed and thrive. Therefore, when organic material like fruits, vegetables, dead organisms or even a feces start to decompose and smell bad, it becomes the ideal breeding ground for larvae of flies. Additionally, flies are detritivores; they play an important role as ‘cleaners’ in our ecosystem by consuming

Whenever there is irritation to our nose membranes because of pollen particles, it results in a sneeze and a whole series of reactions. The chest expands, lungs get filled up with air and we sneeze. After this, the mucus not only spreads but also stays in the air for 10 minutes post-sneeze. Closing of eyelids

Oxygen is a very strong oxidant. It is necessary for mitochondria, the ‘energy plants’ of our cells to work and ‘burn’ glucose to get energy. High doses of it oxidize and damage molecules and tissue of our body. Our body is constantly trying to get rid of the ‘free radicals’ oxygen atoms available to interact,

Sumo wrestling involves wrestlers to be as big in size as humanly possible. In earlier times, Sumo wrestlers were expected to be more wiry and muscular in size unlike what they are now in the twentieth century. Currently, the idea is to have more body mass that allows wrestlers to have more leverage against their

In normal circumstances, people are faced with scary situations which give rise to excess fear in them. The natural response to it is either to take flight or fight the situation. However, sometimes some people are unable to cope with the extreme stress related to persistent fear of a certain situation or object and they

Horseshoe crabs, lobsters and most molluscs have blue blood. Human blood gets its red colour because of haemoglobin where the iron atoms bind to oxygen to give the red colour. Crustaceans or crabs and lobsters get the blue colour from the pigment called ‘hemocyanin’ that carries oxygen in their blood. The copper atoms absorb oxygen