Why does hair not grow on scars?
Skin consists of two principal layers — epidermis and dermis. The epidermis is a continuously self renewing layer. Keratinocyte (a cell producing a protein found in tissues like hair, nails,...
Why are frogs not seen in seas?
Frogs and toads belong to the class amphibia (they live in water and on land).One of the biggest problems faced by these animals is Osmoregulation. When they are in water...
How are flies able to change their flying direction quickly?
A fly, Musca domestica, has four wings joined to its body in the thorax region where the legs are also joined.The flies fly by flapping their wings at a very...
Why does a fan make noise while running on an inverter and not on normal electric supply?
Inverter is an electronic device for converting the direct current (DC) from storage batteries or solar cells into alternating current (AC) to match the domestic supply which is basically 220...
Why and how do milk and water get separated when lime juice is added?
Milk contains an average of 13 per cent solids and 87 per cent water. Milk solids include fat, proteins, carbohydrates, minerals and vitamins.In milk, fat is in emulsion form, proteins...
Why does the ice tray not stick to the freezer of the fridge when the ice tray is kept on rock salt?
The temperature of the freezer box is around -18 degrees Celsius. At this temperature ordinary water would freeze. The ice tray usually sticks to the freezer box because the layer...
Why do earthworms die when salt is sprinkled on them?
Earthworms are grouped under the animal phylum Annelida, which was derived from the Latin word, anellus meaning ‘little rings.’ As this name implies, the body of an earthworm seems to...
How does the ant move up a wall, like the lizard?
Almost all insects have three pairs of legs, and each leg is segmented. The terminal segment of the leg is known as pre-tarsus. The pre-tarsus of insects bears a pair...
Why do flightless birds such as ostrich and emu have wings?
Flightless birds are grouped under Ratitae. Generally ratites are large which have independently lost the ability to fly. These birds are found in South America, South Africa, New Zealand and...
Why do people have red eyes eyes in flash photographs?
Red eye reflex is seen in some flash photographs as flash photographs are taken in dull light conditions. The pupils of the subject are dilated as the ambient light is...
