Why don’t women have beards? Hair has different uses in different mammals. Development of hair in adult human beings is regulated by sex glands. In males, the sex hormone causes hair growth on the face like the beard and moustache. But in women, sex hormones...
What makes the planet Saturn special? Saturn has two special features. One is that it is surrounded by a set of bright, shining rings. This makes it a beautiful sight to behold. Another factor is that Saturn is the lightest of all the planets. It...
Why is Neptune blue? The presence of methane gas in the atmosphere gives Neptune its blue colour. Methane absorbs the red colour in sunlight. Because of this, the light coming from Neptune’s atmosphere appears blue. Like Neptune, earth also has a blue colour.
How does the seismograph measure an earthquake? Seismographs record the vibrations of the earth. It is a delicately hung weight which remains still when an earthquake occurs. But the post which holds it, moves. There is a chart which is attached to the post under...
Which dinosaur had the largest feet? Many dinosaurs had large feet. Sauropods like Brachiosaurus had huge front feet which measured one metre in length. Some of the fossilized footprints of sauropods were so big that one can sit in them. A dinosaur’s feet had to...
How was the Grand Canyon created? The Grand Canyon was made by the Colorado River. The waters of the river cut the great gorge in a process that took thousands of years. The process continues even today. The Grand Canyon was discovered first in 1540...
What are Pterosaurs? Pterosaurs were the first reptiles to take to the skies. They lived for 166 million years but became extinct at the end of the age of dinosaurs. Pterosaurs came in many sizes, the biggest being quetzalcoatlus. It had a wingspan of more...
Where do asteroids come from? Initially it was believed that asteroids were remnants of another planet which had come very close to Jupiter and was pulled apart by Jupiter’s gravity. But now it is believed that they are a collection of lumps that failed to...
What is the length of the human intestine? The human intestines are 3 m long. Vegetarians supposedly have longer intestines than meat-eaters. In meat-eating animals, the intestines are shorter as there is less digestive work to do. Part of the digestion has already been done...
What is a wire bridge? The Brooklyn Bridge in the United States is a good example of a wire bridge. The famous bridge is located in New York. It was the first suspension bridge built using steel cables which are able to carry big loads....
