Snake Venom free essay sample

Intro Each year around 1 million people world wide are bitten by snakes, and around 30,000 to 40,000 of the snake bite victims die from the venomous injection of a venomous snake. Of the 2,000 species of snakes, about 400 are venomous. The cobra, coral snake, and rattlesnake are common examples of venomous snakes. (Snake2). Knowing this information and more can possibly save yours or somebody elses life when put into a situation when you have been bitten by a snake and cant identify it, this paper will educate you on what to do in case of a snake bite and how the venom works on the human body. Snake bite- the wound made by the fangs of a venomous snake or the teeth of a non-venomous one. (Snakebite). Snakes only bite to capture prey or protect themselves when they feel threatened. When they feel threatened they give you warnings to tell you that they are about to strike. We will write a custom essay sample on Snake Venom or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page For example a rattlesnake will shake its rattle, a cobra will raise its hood, and the majority of the snake world will warn you with a loud audible hiss. Ways of Envomation The process of introducing venom into a victim is called envenomating. Envenomating by snakes is most often through their bite, but some species, like the pitting cobra, use additional methods such as squirting venom onto the mucous membranes (eyes, nose, and mouth) of prey animals. (Reptipage 1). There are different types of delivery methods of delivery of venom. First you come to the short fixed fangs of cobras and mambas. These fangs are fixed in the front of the snakes mouth and do not move when envenomating. In exception for the cobras there is the spitting cobra, which shoots out a Jet of venom out of the hollow holes in the fangs. The snake usually aims for the eyes, nose, or mouth as mentioned above. Then we ome to the vipers, which have swiveling fangs, which swing forward like a hinge while striking. Then there are the rear fanged snakes, which most of them are in the colibrid family. These fascinating snakes have fixed fangs in the back of their mouth, which are actually Just enlargened teeth, the strangest of these snakes in the stiletto snake. When the snake goes to strike, the fangs slide out of the side of the mouth and the snake strikes with the side of its mouth. It smacks its head on the victim and the fangs pierce the victim from the side of the mouth. When the snake bites, it chews to et venom flowing. Most of the snakes in this family are mildly venomous and the power of the venom isnt strong enough to do any real harm. Venom Venoms are basically modified digestive Juices, with a clear or yellowish tint to it. The components of venom cause the preys nervous system to malfunction while others break down muscles and blood vessels. Most venoms cause a multitude of effects behind each eye that connect with enlargened teeth modified for injection. (Harvey The Action of Venom Snake venom is a complex protein substance and its exact composition varies from one species of snake to anther. When a snake bites, it generally injects its venom though or near its fangs into the wound. Snakebite can even occur when the snake has been dead recently, or even by the snakes dismembered head because the snakes nerve reflexes are not extinguished for many hours. (Snakebite 2). A neurotoxin venom works to disrupt the function of the brain and nervous system. Classically, such snake venom causes paralysis or lack of muscle control, but it can also disrupt the individual signals sent between neurons and muscles. Such venoms can also attack the bodys supply of ATP, a nucleotide that is critical in energy transfer. Researchers once believed that many snake venoms contained digestive enzymes to make it easier to process prey. Howeve r, this does not appear to be the case; snakes with digestive enzymes in their venom dont digest prey any more quickly. More probably, such snake venom contributes to tissue death by literally eating the tissue away, accomplishing the snakes goal of incapacitating a victim long enough to start eating. Some animals have natural immunities to snake venom and immunities can also be induced through careful applications of processing the venom. This technique is used to make the venom used in snakebite treatments. Because there are around 600 venomous snakes in the world, many nations have venom exchange programs, which ensure that hospitals and treatment centers can provide anti-venom from other facilities in an emergency. (Snakebite 1). Venom Composition Snake venom has a great majority of proteins: some have enzymatic activity, some can block nerve or muscle cell receptors, and some have activity in the protein cascades for coagulation, complement fixation, or inflammation. (Reptipage 1). Most snake venoms contain specific proteins that paralyze the prey so that it no longer oves, interfere with normal blood clotting mechanisms so that the anima goes into shack and then they begin the process of digestion by breaking down the tissues of the prey animal. (Reptipage 1). -roxtcit-y (LD 50) Toxicity of venoms is usually expressed by LD50: the lowest dose that kills 50% of a group of experimental animals. That dose varies not Just between the venoms tested, but also depends on which species of prey animals receive the venom. Generally, the most toxic venom is the one with the lowest LD50. However, some snakes have venoms that are quite specialized for certain types of prey. Few studies have used the natural prey of a snake species, which would involve capturing a number of wild animals. Instead most research has used inbred strains of laboratory animals. rodents. The next factor in assessing the danger of a partiticular species of snake is the dose of venom that is actually introduced into the tissues. Some types of snakes have an extremely efficient mechanism of injection venom with a sing strike; others have poor success in doing so. The amount of venom produced by snakes that is available for secretion with a bite also varies between kinds of snakes, and between ndividuals (usually by size) of any one species (reptipage 1). Symptoms of venomous snakebites. The symptoms vary not only with the type of venom injected, but also with the amount. A snake may release no venom at all, or it may release as much as 75% of the total amount stored in its venom glands. Often when a snake bites in self- defense, it injects less venom than when it attacks its prey. The physical condition of the victim and the location of the bite also affect the severity of the symptoms. A bite into a muscle is less dangerous than a bite into a blood vessel, for example, because oxins in the blood are quickly circulated through the body. General symptoms of snakebite include localized pain and swelling soon after the bite occurs, followed by nausea, tingling or numbness, weakness, and shortness of breath. If victims do not receive treatment within a few hours, they may suffer convulsions, fall into a coma, and die. Even venoms that damage only tissue can be fatal within several days. (Snake venom 2). Listed below are different stages of snakebite symptoms: Paralysis Some proteins secreted in snake venoms are toxins that affect nerves. (Neurotoxins) nd the contractibility of muscle. Most neurotoxins in snake venoms are too large to cross the blood-brain barrier, and so they usually exert their effects on the peripheral nervous system rather than directly on the brain and spinal cord. Many of these neurotoxins cause paralysis by blocking the neuromuscular Junction. In fact, biologists first learned some of the details of how the neuromuscular Junction normally functions by using purified snake venoms in physiology experiments. (Reptipage 2). Shock Many components in snake venom disrupt normal blood flow and normal blood lotting (coagulation). Some common enzymes in snake venoms increase bleeding by preventing the formation of clots, and others by breaking down established clots. Both of these types of enzymes include metalloproteases. Other toxins increase bleeding time by inhibiting the aggregation of platelets, the small odd-shaped blood cells that collect at the site of a tear in a blood vessel and form a plug to close it. Profound loss of blood can cause hemorrhagic shock, and disable a prey animal. When many tiny blood clots form in the bloodstream there is a pathological condition nown as disseminated intravascular coagulation (DIC), which also causes shock. Some enzymes in snake venom set of DIC in the bloodstream of their envenomated prey by interfering with the activity of serine proteases involved in the regulation of Toxins that set off clotting within the blood vessels of envenomated animals can cause both stroke and heart attacks. Infarction is a medical term that means death to tissues because of a block in their blood supply, and clots within the arteries of the neck and brain, as well as the coronary arteries can deprive the blood supply enough to cause infarctions in these organs. Reptipage 3). Death!!!! When the circumstances are right, and enough venom is injected, if you do not receive medical attention immediately after the bite, you will DIE! Types of venomous snakes There are two major types of venomous snakes: 1 . Vipers and 2. Elapids. Vipers include rattlesnakes, copperhead, and water moccasins. Many vipers strike and release their victims quickly because their fangs can shoot venom instantly into the wound. Elapids i nclude cobras, mambas, and coral snakes. The fangs of an elapid snake do not deliver venom quickly; therefore, an elapid frequently hangs on to its ictim and chews, forcing venom into the bite. In most cases, the wound from an elapid causes little pain at first. But later the breathing organs of the victim become partly paralyzed, and the victim becomes sleepy. Venom characteristics and venom delivery (according to family) The venomous snakes are represented in only four families. There are variations in the methods of envenomation according to family. The families are listed below with information included about each of them. Crotalinae (crotalines) Common names of well-known members: Pit vipers, including lanceheads, moccasins, and rattlesnakes. Pit viper venom characteristically contains a potent mix of enzymes that produce an emphatic degree of tissue destruction at the site of the bite. As with most venom, there can be both local and systematic effects. However, unless a bite by a pit viper is dry (meaning no venom injected), there will ordinarily be marked inflammation at the site of the bite and possibly systemic effects. Rattlesnakes range in size from small pigmy rattlesnakes (sistrurus) to large (many species of crotalus, such as the Eastern diamondback, (crotalus adamanteus) most pit vipers are potentially very active and aggressive snakes. The strike can be lightning quick, measured in one study as less than 50ms. (Reptipage 2). Viperidae (viperids) Common names of well know members: pitless vipers, pit vipers Bites by snakes of the family viperidae often induce local break down of muscle and tissues which may result in permanent deformity in the region of the bite (myotoxic phospholipases). Some types of vipers inject venom that travels through the blood stream and breaks down muscle cells systemically, with relatively little reaction at the site of the bite, but enough muscle cells throughout the body release their contents nto the victims bloodstream to cause a condition know as rhabdomyolysis. In rhabdomyolysis (rhabdo=rod, myo=muscle cell, lysis†breaks apart) the large iron When myoglobin reaches the kidney, the renal system attempts to filter it out of the blood. If the amount of myoglobin is very large, acute renal failure results, and the blood is no longer properly filtered of even normal body wastes by the kidneys.