Category Archives: DO?
161.DO SNAILS LAY EGGS?
Snails are mollusks, which means a kind of animal without backbones. There are two basic kinds of snails: the first includes the snails which have shells; the second, those which are covered merely by a thin mantle. Members of this second group are usually called “slugs.”
All the members of this division of mollusks have one large foot on the underside. Therefore, they are called “gastropods,” or stomach feet. This division also includes the large whelks of the ocean and the periwinkles. The ocean snail measures about 25 millimeters in the shell.
142.DO FISH HAVE HEART?
Sometimes it is hard for us to imagine that creatures which are so unlike us have organs very much like ours that function in the same way. Many people think that because a fish lives in the water and is cold-blooded it must lack various organs, or not have certain senses.
Actually, the anatomy of a fish is very much like that of higher warm-blooded animals. In fact, many scientists believe this similarity is evidence that life on land evolved from life in the sea!
125.DO ALL KINDS OF MOSQUITOES CARRY DISEASE?
Have you ever been out camping or walking in a beautiful country spot, when suddenly everything was spoiled by a swarm of mosquitoes? These little creatures cannot only ruin our pleasure, they can make us quite miserable with their stubborn attacks.
For a long time, man considered mosquitoes annoying and troublesome but that was all. It was not until the end of the century that we began to discover they were dangerous, too.
