What is the carbon cycle? Carbon is continuously being used, removed and replaced by living things. This process is called the carbon cycle. Plants take in carbon dioxide from the air in order to grow. Animals and humans take carbon from plants as vegetables, fruits,...
Could dinosaurs smell? Dinosaurs had nostrils, and fossils of their brains seem to indicate that they had a good sense of smell. This was essential to sniff out food. They might also have used their sense of smell to find a partner. Brachiosaurus had large,...
What is a boll weevil? The boll weevil is a small brown beetle which can ravage cotton crops. It is a native of Central America. Boll weevils have a keen sense of smell. The pest breeds in the cotton plant’s flower buds. They also attack...
What is a nebula? A nebula is a huge cloud of gas and dust in space. Some can be seen with the naked eyes but we can view more through a telescope. A nebula has mostly hydrogen gas and some helium. Sometimes the two gases...
Why do hailstones come in varying sizes? Hail is formed when raindrops pass through a belt of cold air and are frozen during their passage to earth. Single raindrops form small hailstones. Sometimes as the small hailstone falls it meets a rising current of air....
When did people begin to cook food? Except for frying, primitive people were familiar with the different types of cooking that are practised today like broiling, roasting, baking, stewing, steaming, parching and drying. But their cooking was more crude. Animals were roasted whole on a...
Who was Neanderthal man? Neanderthal men probably existed for about 70,000 years in central Asia, the Middle East and many parts of Europe. The men were stocky and had flat skulls. They had long faces with heavy jaws. They used tools like hand axes and...
Why do we need sunshine for good health? Sunshine can destroy fungi and bacteria that live on the skin. It causes the white blood cells which fight infections to become active. It also charges our nervous system by giving the muscles new tone. The ultraviolet...
What is fool’s gold? Fool’s gold is in fact a mineral known as iron pyrite. It is a yellow-coloured mineral with a brilliant shine and was often mistaken for flecks of native gold in rock. Native gold is often found in quartz veins and pyrites....
What are molluscs? Molluscs are animals without backbones. They include snails, octopuses, clams, oysters, etc. They can be found in the tropics as well as the Arctic and in sea or on land. Molluscs have soft, slimy and boneless bodies. The bodies have a covering...
