Spider | Spiders are famous of fears, stories and mythologies of various cultures for centuries. They have symbolized patience due to their hunting technique of setting webs and waiting for a prey, but also evil and malice for the painful death of their poison causes. Web-spinning also caused the association of the spider with creation myths as they appear on the ability to produce their own worlds. In science, spiders have breathing arthropods that have eight legs and chelicerae with fangs that inject poison. Spiders are found worldwide in all continents except Antarctica, and have settled in nearly every habitat except the air and sea colonization.
Spiders are invertebrates. They lack a backbone and they have no internal skeleton. Instead, the entire body enclosed in a hard, protective coating called an exoskeleton. The exoskeleton is made of protein and reinforced by a substance called chitin. Sensitive hairs and spines covering the exoskeleton. Spiders vary greatly in size and color. In height they range from 1/50th of an inch to 3 1/2 inch. Most spiders are gray, black or brown, but some are so vivid colors like green or red and others have colorful markings on their bodies. There are about 40,000 species of spiders, and 109 families have been recorded by taxonomists. Yet there was any confusion within the scientific community about how all these families that are proposed to be classified since 1900.
The spider body has two main regions. The cephalothorax, which consists of a molten head and chest and abdomen. The two areas are separated by a conical section, said stem. At the front of the cephalothorax the eye, usually four pairs, and the mouth. The mouth is adapted to suck spiders do not chew their prey, but instead suck the internal fluids of their victims. Six pairs of appendages on the cephalothorax, a pair of chelicerae, a pair of pedipalps and four pairs of walking legs. The chelicerae end in fangs, which contain a poison that paralyzes or kills prey. Most spiders feed on insects. The larger species feed on small fish, birds and reptiles. The pedipalps are used as feelers, and to hold the prey during feeding. In male spiders, the pedipalps also used to transfer sperm to the female.
Spiders often use lots of silk which they spin. Like other spider species of spiders are terrestrial, although some have adapted to freshwater life by air bubbles underwater and carrying the bubbles with them. Spiders are numerous and occur worldwide. All spiders kill their prey with a venomous bite. A spider bites its prey with its fangs, the long, pointed teeth. Poison, the so-called poison flows through the teeth. The poison stuns or kills the spider its prey.
Spider has no chewing mouth parts. It can not eat its prey by chewing. Instead, the spider sucks the fluids of its prey. A spider can inject special juices out of his mouth on the prey. These juices turn the prey's body into a soupy liquid. Then the spider can slurp her meal. A spider just stuns its prey. Then spins and weaves a silken case around the prey. The spider is prey on its website or put it in a safe place. When the spider is hungry, it has a meal waiting.
The bite of some large spiders can be painful, but most species are too small to break human skin, and only a few are dangerous to humans. The latter are mainly the black widow spider and its close relatives, non-invasive and bite humans only in defense. Their painful bite is followed by faintness, difficulty in breathing and other symptoms, although the bite is rarely fatal, especially if it is caused to healthy adults, medical help should be sought at once.
Spider poison, a less polluting alternative to conventional pesticides as they are deadly to insects, but the vast majority are harmless to vertebrates. Australian funnel web spiders are a promising source as most insect pests in the world have no possibility of any immunity to their poison to develop and funnel web spiders thrive in captivity and are easy to "milk". It is possible to specific pests to be set up by the technical genes for the production of toxic substances in the spin viruses that species, such as cotton boll worms infect. Potential medical applications for the spider poison be examined. Because spider silk is both light and very strong, attempts are being made to produce it in goats and in the leaves of plants.