Which are the poisonous spiders? Not many spiders are poisonous to man. Spiders usually use their poison only to defend themselves. One of the more dangerous spiders is the black widow. Its bite can cause severe pain and illness. It has a red, hour-glass shaped...
What is immunity? Immunity is the ability of the body to resist and fight infections caused by disease causing germs and pathogens. The body produces antitoxins to battle the toxins produced by germs. Acquired immunity is when the body acquires resistance to a disease after...
What are catacombs? Catacombs were underground tombs near Rome. Here was where the bodies of the early Christians who were persecuted by the Romans were buried. The tombs were cut in soft rock in a sacred area surrounding Rome. When emperor Nero began to persecute...
How do we taste food? The human tongue is covered with tiny, wartlike bumps called papillae. The walls of the papillae contain taste buds which are distributed in various zones which correspond to different tastes like bitter, sweet, sour and salty. Smell is also part...
Who discovered the light year? Danish astronomer, Olaus Roemer discovered the light year in 1676. Light travels a distance of 5, 880,000,000 miles in a year. This is called a light year. Light travels at a speed of 186, 284 miles per second. Light year...
Why do people snore? Snoring is yet another effect of gravity. While sleeping, gravity pulls the uvulaa piece of flesh at the top of our throats and other soft tissues which partially block the airway to the lungs. When we inhale, air rushes in through...
Which was the largest city in ancient times? The largest city of ancient times was CatalHuyuk which was in present day Turkey. More than 6,000 people were living there by 6250 BC. They lived in mud-brick houses which did not have any front doors. To...
Where are asteroids found? Asteroids are generally found in a broad ring between the orbits of Mars and Jupiter. This ring is called the asteroid belt. However some may travel outside the belt, occasionally coming perilously close to the earth. There are two small groups...
How do lobsters grow? Lobsters are crustaceans or hard-shelled animals. Lobsters, as we know, have hard shells but still they grow. The reason lobsters moult all their life. Its shell is disposed of whenever it outgrows it. The first year, it moults 14 to 17...
When did people first use full stops and commas? The monks and scribes of medieval times used to produce handwritten and beautifully decorated manuscripts. The scribes began to separate the words with spaces and used other techniques like capital letters, small letters and a system...
