Thursday, December 20, 2012

Bulimia nervosa and Food Poisoning

Bulimia nervosa

 Like anorexia, bulimia is an eating disorder found most commonly among younger women, often those who have had anorexia. Bulimics crave food but fear becoming fat. They indulge in binge eating by consuming vast amounts of food and then induce vomiting and use laxatives. This constant bingeing and vomiting can cause severe medical problems. Sufferers from bulimia require the same medical care as anorexics.

 Food poisoning

This refers to illnesses caused by eating food contaminated by certain micro organisms or the toxins, they produce. Worldwide, the incidence of food poisoning is on the increase. This is probably due to the growing use of convenience foods, such as cook chill meals, and the consumption of fast foods, which are easily subject to contamination by the people who make and serve them. Spores in raw rice, chicken beef, water or milk contaminated faeces are caused by Bacillus cerus and Campylobacter fetus. Botulism and Clostridium Perfinges are through food contaminated with bacterial toxin. Meat or vegetables contaminated by faeces. Amoebic dysentery can caused by food or water contaminated by faeces. Norwalk virus can infect through contaminated shell fishes and the rotavirus can introduced to our system by contaminated water or food. Undercooked poultry or egg can cause Salmonella. Food that contaminated by contact with wounds are the reason for the Staphylococcus.

Monday, December 10, 2012

Obesity and Anorexia Nervosa


 The condition in which the body has so much fat is called obesity. Someone is considered to be obese if their weight is 20 percent over their ideal maximum or if their BMI is greater than 30. Around 30 percent of people in western countries are overweight and around five percent of them are obese. Long term obesity is a serious threat to health. It increases significantly the chances of developing high blood pressure, coronary artery disease, stroke, adult onset diabetes mellitus, certain cancers, osteoarthritis, back pain and varicose veins. Obese patients are advised under medical supervision, to lose weight using a calorie reduced diets and increased aerobic exercise.

Anorexia Nervosa:

 Popularly, but incorrectly, known as the “slimmers’ disease”, anorexia nervosa is an eating disorder found mainly among teenage girls and young women, and only rarely increases. In fact, one in hundred of the women suffer from the condition and increasing to one in twenty in those categories of women, such as dancers actors especially concerned with their bodies. Anorexia may be a phobia about being fat or a symptom of mental illness. Whatever its cause, however anorexia is a serious illness in which the individual starves herself and may die. She not only loses her appetite but, more seriously, fails to have a normal perception of the size and shape of her body- she thinks she is fat even when she is way below her normal weight. The main features of anorexia are as follows; excessive weight loss, over activity, secretive and defensive behavior, being choosy about food, obsessive exercising, tiredness always feeling cold , induced vomiting, use of laxatives, thinning of hair on heat, appearance of Languo (Baby hair) on the body, dry skin and cessation of periods (amenorrhea). Anorexics require medical treatment and counseling.

Sunday, December 9, 2012

Diet and Diseases

Fats in foods are divided into saturated fats found mainly in meat and dairy products and unsaturated fats- found in fish and vegetable oils. Research has established a link between the high level of consumption of saturated fats in northern Europe and USA and the incidence of coronary heart disease, leading to death from heart attacks. Coronary artery disease is caused by the buildup of obstructions called atheromas that contain cholesterol.

Studies have indicated a strong link between diet and the chances of developing certain cancers. Cancers of the colon, rectum and stomach may be up to 90 percent diet dependent and diet may be responsible for up to 35 percent of cancers in western countries. For example, there appears to be a close correlation between levels of fat consumption and incidence of breast cancer. In Japan fat provides 22 percent of energy requirements in the diet and the death rate from breast cancer is four per 100,000 people, in USA, fat provides 40 percent of energy requirements and the death rate is 24 per 100,000. Dietary components linked to cancers include:

Excessive alcohol- cancers of the bowel, liver, mouth, oesophagus, stomach and throat, especially in smokers;

 Fatty and low fiber foods – breast and bowel cancers;

 Pickled foods- stomach cancer;

Salt- cured meat and fish, nitrate- cured meat- throat and stomach cancers.

 Dietary recommendations to reduce cancer risk:

 Eat foods rich in fiber daily.

 Eat fresh vegetables only.

 Eat less fat.

 Consume alcohol in moderation.

 Eat fewer smoked and salted foods.

 Keep weight at recommended level.

Saturday, December 1, 2012

A Healthy Diet

The food that we eat provides us with the energy to power all our body activities, the materials for the growth and repair of body tissues, and the vital chemicals essential for the metabolic reactions that take place in all cells. To be healthy, a diet should:

Consist of a wide variety of natural foods that provide a balance of carbohydrates, fats,, proteins, vitamins, minerals and fibre.

 Supply the body with sufficient energy to meets its needs;

Include only low levels of foods, such as those containing saturated fats, that increase the risk of developing diet related diseases, for instance coronary artery disease.

 Each person has a certain requirement for energy, depending on their age and the amount of activity (or other forms of energy consumption, such as breastfeeding) involved in their daily life. Energy is derived from energy rich foods such as carbohydrates and, to lesser extent, fat. A diet that results in taking in more energy than the body requires in those conditions leads to obesity, while insufficient energy intakes leads to weight loss.

Wednesday, November 21, 2012

Vitamins and Minerals

     Vitamins and minerals are substances required in small amounts, that essential for the normal, healthy functioning of the body normal growth and development, energy productions, body maintenance, and general well being and vitality.

       Vitamins are a diverse group of organic substances that cannot be manufactured by the body – except for the vitamin D (which is produced in the skin when it is exposed to sunlight) and niacin (made in the body from the amino acid tryptophan) – and must, therefore, be obtained from food. Absence of one or more vitamins from the diet will, in time, lead to well defined deficiency diseases such as scurvy, beriberi or ostemalacia. The 13 major vitamins, each of which is found in many different foods, are divided into two groups. Fat soluble vitamins- A,D,E, and K – are found in fat or oil containing foods, and are stored in the liver, so that daily intake of these vitamins is not really essential. In fact, excessive consumption of fat soluble vitamins, usually by taking too many vitamins tablets, can be harmful. Deficiency of fat soluble vitamins is usually caused by disorders that stop the intestine absorbing fat efficiently. Water soluble vitamins- the B complex vitamins and vitamin C are not stored in the body (apart from vitamin B 12). To avoid deficiency, therefore, food containing water soluble vitamins should be eaten each day to keep supplies “topped up”. Because water soluble vitamins are destroyed by prolonged cooking, processing and storage, fresh or lightly cooked foods make the best sources.

     Minerals are simple chemical elements that cannot be made by the body but must be present in the diet o maintain good health. There are 20 minerals known to be essential in small amounts, in addition to carbon, oxygen, hydrogen and nitrogen, which are needed in large amounts to construct the body’s framework. Some, including calcium phosphorous, potassium, sulfur, sodium magnesium and chlorine and some traces of minerals such as iron cobalt copper zinc molybdenum iodine and selenium are also important for mammals.

Wednesday, November 14, 2012

Sleep and Sleep Disorders

    Sleep occupies around one third of a person’s life, although the hours we sleep decrease as we age. A one year child sleeps for about for about 14 hours each day, while a five year old needs around 12 hours. About 90 percent of adults sleep for six to nine hours per night, with most people sleeping 7.5 hours to 8 hours. Less than 6 hours sleep at night generally leads to daytime sleepiness. Elderly people tend to sleep less at night but doze during the day.

    Dreams are the result of mental activity during REM sleep. They are believed to represent the processing of all the thoughts and stimuli that have occurred to a person during the day. They may also form part of the process whereby short term memories are assimilated into long term memory storage. Many psychiatrists believe that dream analysis can reveal emotional conflicts.

      Sleep disorders can disrupt normal daytime functioning or cause sleepiness. Insomnia: Difficulty in falling, or staying, asleep. Around 30 percent of adults suffer from insomnia at some time in their lives. The main cause is stress, although causes include lack of exercise and misuse of drugs. Research indicates that insomniacs actually sleep more than they think but wake more often than normal. Remedies includes reducing stress levels; taking more exercise; developing a regular sleeping routine; and avoiding coffee late at night. Sleep inducing drugs are only prescribed if these remedies fail. Jet lag is a disruption of normal body rhythms caused by long distance flying across. Sleepwalking, sleep paralysis, Sleep deprivation, Sleep apnea, Night terror, Nightmares, Narcolepsy are some of the sleep disorders.

Tuesday, September 11, 2012


What is sleep? Sleep is a state of altered consciousness and not a turning off of the brain. Although sleep appears to be the opposite of wakefulness, these two stages have a lot in common. Thinking and memory are active in both states, and a sleeping person is sensitive to their crying baby. Studies of sleeping deprivation have shown that sleep is a fundamental need that human cannot do without it. The brain needs periods of sleep in order to rest repair itself and process information received during the period of wakefulness.

The brain produces electrical impulses or brain waves which can be detected using electroencephalography (ECG). Studies using EEG from the 1950’s onwards showed from the patterns of brain waves that sleep can be divided into two distinct stages which alternate in cycles of around 90 minutes throughout the 8 hours sleep period. The chart below shows how a sleeper passes repeatedly through these two states, about every 90 minutes, during an 8 hours sleep period.
The first state is non rapid eye movement sleep (NREM) which takes up about 80 percent of the sleep period, during NREM sleep, the sleeper becomes relaxed and drifts into deeper and deeper sleep. The depth of NREM sleep is measured in four stages of progressively greater depth of sleep. Stage 4 is the deepest when body metabolism is lowest and brain activity least. Dreaming does not occur during NREM sleep.

After 60- 90 minutes, the second stage of sleep begins. The brain becomes more active with wave patterns resembling those of an awake person, temperature and blood flow increase, and the eyes move around beneath the closed eyelids, giving this sleeping state its name of rapid eye movement (REM) sleep. Dreaming takes place during REM state of sleep.
The first REM period lasts for about 5-10 minutes but as the chart shows, the length of REM periods increases as sleep continues. Deep NREM sleep is believed to be the time when the brain rests and repairs itself; REM sleep is when the brain analyzes the day’s events and sorts out emotional problems some researchers believe REM sleep not to be Sleep at all but a third state of existence in addition to sleep and wakefulness.

Wednesday, August 15, 2012

Human Mind

The human mind is the totality of all conscious and unconscious mental processes that have been occurred or are occurring in the brain. Mind disorders, from mild emotional disorders to severe illness, are studied and treated in various ways. Psychology is the scientific study of the mind and behavior. Psychology involves research into feelings, intelligence, learning, memory perception, personality development, speech and thought. Psychologists may also diagnose and treat mental, behavioral or emotional problems through psychotherapy although since they lack medical qualification. Psychotherapy is the use of psychological methods to treat mental behavioral or emotional problems such as neuroses and personality disorders. Treatment is based on the relationship between sufferer and psychotherapist. Following the framework of the type of therapy used, they talk about symptoms and problems in an attempt to find a solution. Psychiatry is a branch of medicine concerned with research into, and the prevention, diagnosis and treatment of mental illness. Psychiatry sees mental disorders as medical conditions. Psychiatrists are medically qualified and may use psychotherapeutic drugs to treat patients. Psycho therapeutic drugs used in the treatment of mental disorders, these can be very effective in the alleviation of symptoms both long and short term although some carry risk of dependence.

Monday, July 30, 2012

World conservation strategy

Plants and animals are unaware of Political boundaries conservation must be based on worldwide strategies. In 1980 the World Conservation Strategy was launched by IUCN (International Union for Conservation of Nature and Natural Resources), WWF (World Wildlife Fund) and UNEP (United Nations Environment Programme). It said that conservation of three factors was needed: 1. Life support cycles, water, soil and air; 2. Species of plants and animals; 3. Genetic diversity. This document became the basis of conservation policies in over 50 countries.

In 1991 IUCN, WWF and UNEP launched caring for the Earth, an updated policy document setting targets and suggesting some methods of approach. IN 1992 the Earth Summit in Rio was attended by many heads of governments, who pledged to implement much of caring for the Earth, its strategies were largely embodied in the Biodiversity Convention ( Although it was not signed by USA). Many of those good intentions have since been watered down or bogged down, but the idea survives and a number are gradually being implemented with a world system of biosphere reserves and heritage sites.

Thursday, July 5, 2012

Coral reefs and Mangrove Swamps

Coral reefs are found where the average annual temperature of the sea does not drop below 21.C. they are the richest of marine environments, estimated to contain one third of the world’s fish species and up to 500,000 animal species in all. Reef corals can only thrive in shallow water, so are often close to land, and therefore at special risk from human activities. Dangers include pollution; dredging and removal for construction purposes; damage by collection of coral and other invertebrates as tourist trophies; and collection of fish for the aquarist trade, which has already wiped out some species of colourful reef fish.

 Mangrove swamps occur in tropical regions where soft sediments are covered with sea water. In cooler areas salt marshes take their place. Both types of environment are rich in species. Mangrove swamps are the nurseries for many kinds of open water tropical fish; salt marshes are feeding grounds for the worlds migrating waders and water fowl. Yet both environments are regarded with disfavor by the majority of human kind and there has been greater destruction of mangrove swamps than of any other habitat type. Currently about 165, 000Km2 of mangrove forest remain, but almost all are under threat largely from pollution, which in some cases causes harmful mutations, and from expansion of farming.

Sunday, June 24, 2012


The wetland ecosystem- rivers, streams, lakes, ponds and swamps- is under threat. Currently covering about 6 percent of the Earth’s surface, wetlands are shrinking rapidly. Destruction of wetlands may seem to bring nothing but benefit. Draining a marsh creates fertile land for cultivations and reduces breeding areas for insects such as mosquitoes. Damming a river provides a water supply, and may mean a source of power as well.
But many changes to water system carry seeds of disaster.
 The Aswan Dam on the upper Nile, completed in 1963 and fully effective by the 1970s, was meant to regulate the river’s flow and provide hydro electric power. However, the traditional fertility of the Nile valley was dependent on over 100 million tones of silt deposited annually as the river flooded. The silt is now silting up the artificial Lake Nasser, forcing farmers downstream to rely on fertilizers, and robbing local brick makers of raw materials; around 35 percent of Egypt’s cultivated land is suffering from salination. Deprived of nutrients, the fish stocks of the eastern Mediterranean are declining while the Nile delta is being eroded steadily. Schistosomiasis is a disease common in newly irrigated areas, has spread explosively, causing debilitation and death; in 1990 between five and six million people were affected.
Surviving wetlands are often badly damaged: by engineering schemes; by eutrophication, when nutrients flow off the land causing huge growths of weeds that over whelm other plant life; by pollution from sewage or toxic industrial waste; or by thermal pollution from water used for cooling.

Tuesday, June 19, 2012

Habitats in Danger

Habitat destruction is the greatest threat to plant and animal species worldwide. In some cases, such as felling of tropical forests or draining of wetlands, damage is frequently done under the impression that the environment is being improved for human food production or habitation. In others, lack of understanding of the importance of particular environment in the life cycles of certain species has led to their downfall. Drainage of mangrove swamps, nurseries for many kinds of fish, falls in to this category.

Sometimes wetland areas are seen as places where disease carrying insects breed, so they are drained without thought of their importance to the environment as a whole. Forests are felled because of the value of the wood they contain, regardless of the fact that they act as a water holding system, without which rivers may run faster in rainy seasons, causing soil erosion in their upper reaches and problems of silting as the river approaches the sea.

 In some areas, even nonessential human demand is regarded as paramount –for example, the breeding beaches of marine turtles in many parts of the world have been sacrificed to holiday homes and hotels, used by a comparatively small number of wealthy visitors. Although experience should show that environmental change often has far reaching effects not foreseen in the early stages of change, mankind seems to be at many instances incapable of learning.

Sunday, June 17, 2012

Human and other living creatures

From the time when human beings first began to grow crops and live in settled communities, their numbers increased fairly steadily until about 1700. Shortly after this the industrial revolution led to a doubling of the population in about 100 tears. In 1800 the world‘s population was around one billion.

By 1990, the numbers had risen to over five billion people will be looking for shelter and food somewhere on the earth. One species cannot increase explosively without affecting all the others. Since about 1700, at least 300 species of vertebrates have become extinct. Now a days we can observe in detail most creatures that are being lost, and the estimate is between 50 and 100 species a day. If the present trend continues at least a quarter of all living things will have disappeared before the human population reaches its levels out, probably in the middle of 21st century.

Monday, June 11, 2012

Extinction of Plants

Plant extinctions have followed the same pattern as animal extinctions. Destruction of environment, particularly on isolated islands, has led to the most dramatic losses. On Hawaii, for example, about 300 plant species have become extinct within the last 300 years. On St. Helena, only 20 of over 100 species of native plants survive and of these 15 are in danger of extinction. It is said that of Barbados all native trees were felled within 40 years of the island’s discovery by European.
Just as an animal species may depend on one plant for survival, the reverses may also be true. For instant, the dodo tree, once abundant in Mauritius, has been reduced to 13 very aged trees since the extinction of the dodo, which ate and dispersed its seeds.
Commercially valuable plants have often been exterminated by over exploitation. Mauritius ebony and Sanfernandez sandalwood are both extinct, examples of felling without provision for regrowth. The wine palm of Dominica, tapped to make spirit in a way that killed it, became extinct in the 1920s.
Habitat destruction is the greatest threat to plant and animal species worldwide. In some cases, such as felling of tropical forests or draining of wetlands, damage is frequently done under the impression that the environment is being improved for human food production or habitation. In others, lack of understanding of the importance of particular environment in the life cycles of certain species has led to their downfall. Drainage of mangrove swamps, nurseries for many kinds of fish.

Tuesday, June 5, 2012

Domesticated Animals

When an animal species is domesticated, it is changed in many ways from its wild ancestors. it may become bigger, stronger and more fecund than the ancestral form. Remaining wild animals are regarded as weeds to be intractable and may have characteristics that have been bred out over generations.

Camel: Date of first domestication uncertain, perhaps by 4000BC. Dromedary, one humped camel unknown as a wild animal. Bactrian camels endangered.

Cat: First domesticated before 1500 BC. Now greatly reduced in the wild.

Cow: Firstly domesticated about 400BC. The wild ancestor, the aurochs, became extinct before 1630.

Donkey: First domesticated about 3500BC. Now extinct over almost all of its former range. Remaining wild asses endangered.

Goat: First domesticated about 7000BC. Now found only in the most remote mountainous areas.

Horse: First domesticated about 3500 BC. Now extinct in the wild: several hundred przewalski’s horses survive in zoos round the world.
Pig: First domesticated about 7000BC. Almost, the only domestic animal that still survives in significant number in the wild.

Sheep: First domesticated about 8000BC. In Europe reduced to wild populations in Corsica and Sardinia. Elsewhere found in remote mountain areas.

Wolf: The first animal to be domesticated, before 10,000 BC. Once the most widespread mammal now reduced to strongholds in remote places. No longer found in most of Europe; numbered in tens in those western European countries where it survives.

Domesticated animals would seem to be in the least danger of extinction. However, in a world where efficiency of production rules supreme, many domestic breeds, slower in growth or less productive in the amounts of meat or milk they provide, have disappeared in recent years. Attempts are now being made to rescue the genetic heritage they represent, for they may be of use in the development of future breeds.

Thursday, May 24, 2012


Each living thing is unique, different in details from all others. However, individuals may be grouped into kinds or species, which are defined as assemblies of organisms that in nature are capable of interbreeding freely but are unable to breed with any other species. The exact number of species of plants and animals is unknown, for more are being discovered all the time. To date, over a million of species of animals and a quarter of a million species of plants have been described and named. Estimates vary as to how many remain to be recognized. A few researchers suggest up to 30 million, but most biologists believe that around eight million are so far unknown. The figure may be raised by recent findings that the deep sea, hitherto thought to be sparsely in habited, could contain up to two million new species.

This huge diversity of living things has come about because each within its environment occupies a niche that is different from all of the others. The differences may often be slight but no two creatures or plants can make identical demands on their habitat. Recent work has shown that in a species rich environment the use of the Sun’s energy is more efficient than in a species poor habitat. Within an environment, species are largely interdependent. If a species should be lost rapidly, there is likely to be a knock on effect as other plants and animals feel the consequences. The pattern of life in the whole are is changed and probably impoverished.

Wednesday, May 16, 2012

Air-borne and acquatic mammals

Most mammals are firmly based on the ground or in the trees. Some can glide from tree to tree on outstretched flaps of skin, but only the bats can really fly. Their wings are supported on long fingers and run along the side of the body to take in the back legs and tails well. They are nocturnal and find their way about by echolocation – sending out high pitched sounds and listening for the echoes coming back from nearby objects. They can pick up the echoes from flying insects which enables them to change course to catch them.
Many mammals live in water, but most have to return to land to breed. Only the whales and sea cows are fully adapted for life in the water. Their front limbs form flippers and their tails form lobe like flukes. Hind limbs are absent, apart from some skeletal remains inside the body. The animals mate and give birth in water, and the only thing that indicates a terrestrial origin is that they still breathe air.

Monday, April 30, 2012

Types of Mammals

In terms of reproductive behavior, mammals fall into three groups- the egg layers, the pouched mammals and the placentals. The egg layers or monotremes, show several reptilian features and are represented only by the platypus and the echidnas. The pouched mammals, or marsupials, are confined mainly to Australia and New Guinea. They are born at very early stage – the new born red kangaroo is about the size of a broad bean- and continue their development while feeding on milk in a pouch on the mother’s body. Placentals, which make up the vast majority of living mammals, give birth to their young at a much later stage of development. While inside the mother’s body the offspring are nourished by the placenta, through which food and oxygen pass from the mother’s blood stream to the foetal blood stream. Many placental babies are so well developed by the time of birth that they can run about almost as soon as they are born.

Man has domesticated many mammal species for both work and pleasure, and has also created many different new breeds. Small mammals, especially rodents such as mice, gerbils, hamsters and guinea pigs, make excellent pets for children. Among slightly larger animals, cats and rabbits make good pets. Dogs were the first animals to be domesticated, probably over 10,000 years. Their ancestors were almost certainly a race of small wolves that lived in Southwest Asia. There are now well over 400 recognized breeds of dogs, including a wide range of working and sporting dogs as well as the more familiar pets.

Horses were first domesticated more than 4,000 years ago, when at least two breeds of wild horses- the Tarpan and Prexewalski’s horse – roamed the steppes of central Asia. One or both of these may have contributed to the domestic horse. Many breeds of horse now exist, from tiny ponies to the great shire horses once common farm animals and now making a comeback as draught animals.

Thursday, April 26, 2012


       Mammals are generally considered to be the most advanced group of animals; this is the class that contains man and the ape. All mammals have relatively large brains and a greater capacity for learning than most other animals. Unlike that of a reptile, the lower jaw of a mammal consists of a single bone, the dentary, on each side. This of great help to paleontologists in identifying fossil skeletons. Mammals first appeared on the earth a little over 200 million years ago, the descendants of some small insect eating reptiles, but they did not come to prominence until the extinction of the dinosaurs about 65 million years ago.

        When the dinosaurs disappeared, mammals were able to investigate many different ways of life and evolve in different directions. Since then thousands of species have come and gone many of them weird experimental forms such as the shovel lipped elephant and the giant Baluchitherium. The latter looked like a cross between a rhinoceros and a giraffe and, with a weight of perhaps 30 tones, was the largest of all known land mammals. Today, however, there are only about 4,100 mammalian species. The mammal teeth vary according to the animal’s diet. Carnivores have sharp edged cheek teeth that are suitable for slicing through meat. Herbivores, in contrast, have flat grinding teeth. Rodents have chisel like front teeth.

Saturday, April 14, 2012


Birds evolved from reptilian ancestors about 140 to 150 million years ago. The earliest known bird is the Archaeopteryx, several fossils of which have been found in Germany; about the size of a pigeons. Archaeopteryx had many reptilian features, including toothed jaws and lizard like tails, but it also had feathers and was undoubtedly a bird. Birds are the only animals with feathers, which clearly evolved from reptilian scales. As well as aiding birds in flight, feathers help them to maintain their bodies at a constant high temperature. Each feather has a horny shaft, a rachis and numerous branches, barbs. The barbs of the outer feathers are linked together by hooked branches, barbules. The wingtip feathers are primary or flight feathers; those nearer the body are secondary feathers.
 Modern birds have no teeth and with their front legs turned into wings, their bills or beaks have to collect and process their food. The bill of each species is admirably suited to its diet. Many birds have lost the power of flight during their evolution. The ostrich the world’s largest living bird- grew too big to fly. However, its size and fast running in short burst give it plenty of protection. Rheas in South America, emus in Australia and cassowaries in New Guinea have evolved in similar ways and have all come to look alike, although they are not closely related. Birds living on islands with no mammalian predators often became flightless. The kiwi of New Zealand is a familiar example. Some of these birds died out when man introduced cats and other mammals, and many more are now in danger of extinction. Penguins cannot fly in the air, but they use their powerful wings as flippers to fly underwater.

Wednesday, April 11, 2012

Fangs and Venom of Snakes

         Venomous snakes inject their venom with fangs. These are enlarged teeth – at either the front or the back of the mouth. The venom is produced in glands in the roof of the mouth. Rattle snakes and vipers have very long fangs that are folded back along the roof of the mouth when not in use. The longest fangs, up to 5cm long, belong to Africa’s gaboon viper. Snakes can swallow prey much fatter than their own bodies because they dislocate their jaws to give an enormous gape. Furthermore the ligaments stretched between bones are extremely elastic. Using their teeth like ratchets, they gradually work their jaws forward to engulf the prey. 

        Only a few venomous snakes are really dangerous to humans, but the most poisonous ones are not necessarily the most dangerous because they may be timid or not live in the places where they don’t be in the contact with the people. Many number of peoples were killed by the most dangerous snakes are primarily the Indian Cobra and saw scaled viper. Both kill thousands of people in Indian and Southeast Asia each year, although exact figures are impossible to obtain. The puff adder is probably the most dangerous of the African snakes, while the western diamond back rattlesnake kills more people than any other North American snake.

Tuesday, April 10, 2012


The reptiles came into being about 300 million years ago; descending from some kind of amphibian ancestor that gained a scaly waterproof skin and the ability to lay shelled eggs that could survive on land. Most living reptiles still lay eggs, although some give birth to active young. They live on land in fresh water and in the sea, and between them they eat almost every kind of food. There are about 6000 living species, of which some 3000 are lizards and 2700 are snakes. Turtles, tortoises, crocodiles and alligators make up the rest of the class.
Reptiles are said to be cold blooded because they have no internal mechanism for maintaining a constant temperature like birds and mammals. Many however can adjust their body temperatures by varying their behaviors. They bask in the morning sun to warm up, hideaway in the midday heat and then come out again in the evening.
The lizard like tuatara is the only living member of a lineage more ancient than the dinosaurs, but it has hardly changed since its relatives died out of over 200 million years ago. It lives only on a few off shore islands of New Zealand, having been exterminated elsewhere in the country by introduced predators.

Tuesday, April 3, 2012


The amphibians were the first back boned animals to make a go of life on land, but even then they had to return to the water to breed- just like most of today’s amphibians. They evolved from a group of air breathing fish whose fins became transformed into legs capable of supporting their bodies. With length of 4 meter and more, some of these early amphibians were very much larger than their present day descendants. Amphibians feed mainly on insects and other invertebrates, although the larger species also eat small vertebrates. Most frogs and toads catch their prey with a long sticky tongue, which is flicked out at high speed. The lungs are not very efficient and much of the animal’s oxygen is obtained through the thin skin, which is well supplied with blood vessels. The thin skin restricts the amphibians ot damp habitats.

The Amphibians are divided into numerous orders, but only three of these have living members. The gymnophiona contains the worm like caecilians of tropical areas. The Urodela contains the tailed amphibians the newts and the rather more terrestrial salamanders. The Anura contains the frogs and toads, which are tailless and mostly adapted for jumping. In Europe, the name frog is applied to amphibians with smooth skins, while toad is applied to those with warty, often drier skins. This distinction, however, is not always made elsewhere in the world.

Friday, February 24, 2012


Almost all spiders possess venom, which may inject into their prey through sharp, hollow fangs. Few spiders are able to pierce human skin, but about 30 species out of a total of about 40,000 can cause severe illness or even death if they bite people. However, spiders are not usually aggressive and have rarely been drawn to bite unless it is provoked. The very notorious spider is undoubtedly America’s Black widow. Although its fangs are very short, it manages to get them through the skin to inject venom which is volume for volume, about 15 times more poisonous than rattle snake venom. The spider obviously injects a much smaller amount than a rattle snake but it causes severe pain and nausea, and has resulted in many deaths over the centuries. The closely related red widow in habits the sand pine scrub of southeast Florida. Similar spiders are found in southern Europe as well as in most other warm areas of the world.

The brown recluse spider from the southern USA injects venom that destroys blood and other tissues. It has caused some deaths. The Sydney funnel web is Australia’s deadliest spider, and is particularly dangerous because it often makes its home in gardens. The most deadly South American spider is the wandering spider an aggressive hunter that has been known to kill children. It occasionally turns up elsewhere, having travelled in crates of bananas. Its fangs are over 400 long but the longest fangs –up to 12mm long- belong to the bird eating spiders or tarantulas. Luckily, these big spiders do not have particularly strong venoms. Antivenins are now available to treat victims of most of the dangerous spiders. Provided they are given quickly they should result in almost immediate recovery.

Sunday, February 19, 2012

Insect produce

Insects provide us with a surprising number of commercially important materials. Cochineal, which is widely employed as a red food dye, and shellac, used in varnishes and polishes, are both obtained from scale insects. The honey bee supplies us not only with honey but also with bee wax for polishes. Silk, most of which is produced by the silk moth bombyx mori in a process that was for centuries a closely guarded Chinese secret, is one of the finest natural fibers in existence, and has long been valued for fine clothes because of its shiny appearance and light weight.
Natural pesticides
The role of ladybirds in controlling aphids is well known, but there are many other pest killing insects. Gardeners can now control whiteflies and other greenhouse pests by buying a supply of minute parasitic insects that attack and kill the pests. The big advantage of these biological control agents is that they leave no harmful residues on the crops. Insects can also be used to control weeds. For example, the larvae of a South American moth called cactoblastis successfully rid Australia of the introduced prickly pear cactus.
Insects as human food
Locusts have always been eaten in Africa and other warm areas. Fried in butter after removal of their wings and legs, they are said to be very tasty and nutritious. Honey pot ants, which are full of stored honey, are eaten by many desert dwellers. Witchetty grubs, eagerly sought by Australian aborigines, are wood boring caterpillars. Many beetle grubs, including the mealworms often used to feed birds and other pets, are also widely enjoyed by indigenous peoples, among whom they are considered highly desirable food, especially when fried.

Tuesday, January 17, 2012

Travel in any of the explored or unexplored places

Travel in any of the explored or unexplored places:

The tedious work of the people does not give permission to them to think further than the routine, and go natural with their own weird way they imagine. This actually put all of us in quandary to decide what to do with the plan that can be implemented. The people always think of getting out of this monotonous life in a better way. People, who are still confused, thinking of numerous ways of breaking shackles of the daily frowning lives, can go to a natural place to travel the beauty made by the nature itself. For this purpose, one can go with his family, by means of some holiday package or some other convenient way.

Due to the hectic schedules, one can go for a trip after a long time. We all has already experience the pleasure of going for a trip with friends or family. Therefore, if you are thinking to go out, then this would be the best time, which ultimately brings out the most excellent part of us. The most important thing in a trip is that it sets a person free from any of his worldly tensions, and travel allows him to enjoy the life in a complete way.

Therefore, before the time gets over of the boring life, pamper yourself for a wonderful travel to any of the holiday spots or natural spots. You will be realized a number of benefits of any small meaningful holidays. You be get relaxed without any of the tensions of the outer world. Even some researchers say that the most excellent of a man comes out after an eventual and happy break from the daily hectic work.

You can take help of any of the holiday planners that can help you out in deciding a wonderful place for your trip. You can also take the advantage of numerous websites, which can help you to decide the best place, which can make your travel successful. Through the use of these websites, you can plan your destination by yourself, as they can give you a very clean idea of the places that you can visit. There are numerous unexplored destinations also, that can convince you to go there. If you have something wild in your mind, then you can also make your mind in going to an unexplored place, which would be both natural as well as pleasing. As the overall target is to go for a trip that can give you a break, ultimately providing you the energy for your further works in the life.

Summary: For having a break from your fast and busy life, you can travel in a new place with your family or friends. Going for a trip can relax you from your busy life.

Friday, January 13, 2012


The invertebrates are animals with no back bone. Some have no skeleton at all, but many have external skeletons or shells that give them a rigid shape and provide anchorage for their muscles. There are about thirty major groups or phyla of invertebrates, although the great majority of species belong to just two phyla- the Mollusca and the Arthropod. The later includes the insects, spiders, crustaceans and several other groups, all of which have segmented bodies and jointed legs. The majority of invertebrates are quite small, but examples of the largest the giant squid are known to have been as much as 15m long and possibly well cover a tone in weight, which is considerably more than most vertebrates.

Molluscs Molluscs are soft bodied animals with no sign of segmentation. Most have chalky shells. There are over 60 000 species, three quarters of which are slugs and snails. Bivalves, such as cockles and mussels, and the squids and their relatives make up most of the rest.

The crustaceans include animals as diverse as lobsters, barnacles and water fleas. All have hard outer skeletons impregnated with lime, and several pairs of legs. Most of the 30000 or so species are marine, but many live in freshwater and woodlice live on land.


The insects are the only type of invertebrates to have wings, although they are not all winged. Adults have three main body sections and three pairs of legs. Well over one million species are known, living in almost every habitat, although there are only a very few that live in the sea.
Spiders belong to the arthropods family. They have two main body section and four pair of legs. All are carnivorous and kill their prey usually insects with venom. Many species snare their prey with extremely intricate silken webs.

Tuesday, January 10, 2012

Finding Food

Food is the central to an animal survival. Most each plants, for among living things the bulk generation vastly exceeds the biomass of the animals. Among these plant feeders, most of the specialists and, for example, over 100 different species of insect may depend on one tree. They vary, however, in their needs for leaves, pollen, bark, wood or roots and their different times of feeding. Larger animals are usually less selective, but there are exceptions- such as the three-toed sloth, which feeds only on the tender shoots and leave of Cecropia.

One feeding stratagem that has proved highly successful for large plant eating mammals is chewing the cud. Cud chewers take in food quickly and pass it directly to a holding comportment of the stomach. Later it returns to the mouth for complete mastication. When it is swallowed for a second time it enters another part of the stomach where digestion begins. Normally plant feeders are exposed to predators while gathering food, but a cud chewer can find itself a safe, sheltered place for the lengthy process of mastication. The success of this stratagem can be seen in a comparison of medium sized plant feeders; six species of horse like animals and two tapirs do not chew the cud, where as 40 species of deer and over 110 species of cattle, sheep and antelope are all cud chewers.

Monday, January 9, 2012


Animals have many ways of surviving harsh weather when, because of heat and drought or low temperatures, the water and food supplies fall. Some simply move to where food is still abundant. The lives of some African herbivores are a continuous migration following food supplies. Many others animals go into a state of torpor, which is referred to as hibernation in cold conditions or aestivation in hot, dry climates.

Cold blooded animals, such as insects, amphibians and reptiles, hibernate without any great physical changes. They find a place where the temperature will not fall below freezing. As their surroundings cool, their bodily activities drop to a level where they are using little energy to stay alive.
No large mammals hibernate truly, but many small species, including some insectivores, bats and rodents, do. They must make enormous physiological changes in order to survive, perhaps for months, without water or food. To conserve energy, their body temperature drops by many degrees, their heart beat and blood circulation is reduced to a very low level and their breathing almost stops. Hummingbirds are able to drop into a torpid state when not in flight; nestling swifts may do so if food is not available, but the only bird known to hibernate fully is a poor will, and even it has periods of torpidity lasting days rather than months.


Every one of us knows the reason for migration.  Birds are, to most people, the most obvious migrants. Their travels usually take them north in spring and south again in autumn. The northern land masses have a far greater are than the southern ones, so adequate breeding territories may be set up or, for  sea birds, nest sites found near to food rich waters, also, the long hours of day light of the northern summer give more time for feeding hungry young than would be possible in short, tropical days.

Migration routes were probably established at the end of the Pleistocene period, and each species follows its own pattern of movements, led mysteriously but certainly, land marks, the stars and planets, and even by the Earth’s magnetic field. Some young birds learn their migration route from their parents. Others, such as young cuckoos, have no such guidance. Flying alone, they have only their innate knowledge of direction and distance to take them to their winter home, a strategy that gives them a chance to survive to be among the next year’s breeding population.

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Bring the Fresh

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Price Of Gold

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Sunday, January 8, 2012


Among flesh eating animals, the use of venom is a method of subduing prey that cuts across taxonomic boundaries. Generally, venomous animals are small, slow-moving or fragile. The delicate tentacles of a Portuguese man of war, for instance, deliver paralyzing stings. Were it not for this, it would be thrashed to pieces by the struggles of its prey. With a poisonous bite, short sighted spiders prevent insects escaping. Snakes such as vipers or cobras use venom to still fast moving small mammals.

While each kind of venom is chemically slightly different, almost all have a dual function. The first is to act on the nervous system of the prey, paralyzing it and preventing its escape. The second function is digestive, for venoms contain proteolytic enzymes that break down animal tissue. A spider has no need to chew its food; after a while it merely sucks up a largely predigested meal. The mouse eaten by a venomous snake is at least partly digested by the injected poison.