Functions of the skeleton - Student Book pages 4 and 5
Your skeletal system
Your skeleton is made up of 206 bones, which support you, allow movement and protect your internal organs. Each type of bone has a different function: for example, your skull protects your head, your vertebrae let you stand upright and the many bones in your hand give your fingers great flexibility. Bones also store calcium and the bone marrow inside produces blood cells.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
Images of the human brain
These four images of the human brain show it viewed from the side (top left), in cross-section (cut in half through the middle, top right), from above (bottom left), and from below (bottom right).
Photo Researchers, Inc./Professor Peter Cull/Science Photo Library
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
© Microsoft Corporation. All Rights Reserved.
Heart
The human heart is a muscular organ about the size of a fist. With each beat of the heart, oxygen-containing blood is pumped throughout the body. The heart contains four hollow chambers that act as temporary storage boxes for blood. The right atrium and left atrium fill with blood from elsewhere in the body. The left ventricle and right ventricle collect blood before pumping it out to other parts of the body.
© Microsoft Corporation. All Rights Reserved.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
Muscles and Bones - Student Book pages 6 and 7
Video clips used during the lesson:
1. Muscles and Bones with skin all around click here
2. The Skeleton Dance click here
Drugs - Student Book pages 8-13
When you are ill, your parents probably give you some medicine to bring your temperature down or to take the pain away. When you have a bad infection, your doctor prescribes an antibiotic for you. The medicine and the antibiotic contain drugs that affect the way your body works or help you fight disease.
WHAT TYPES OF DRUGS ARE THERE?
A pharmacist’s shelves seem to be full of drugs. Some drugs can be bought by adults over the counter, but most need a doctor’s prescription. As well as painkillers and antibiotics there are drugs to help people sleep, tranquillizers to relieve anxiety, medicines to stop coughs, nasal drops to clear blocked sinuses, steroids to reduce inflammation and drugs to lower blood pressure. The list seems endless and it is easy to believe that there is a drug to help every health problem we have.
Modern drugs are made artificially by pharmaceutical companies. Each drug has a chemical name and a trade, or brand, name that belongs to the manufacturer. For example, paracetamol, or acetaminophen, is the chemical name of a painkilling drug and Panadol, which contains paracetamol, is one of the trade names you may find in a pharmacist.
WHICH DRUGS RELIEVE PAIN?
Until the 20th century, drugs for relieving aches and pains were usually made from plants. Opium from a type of poppy was widely used, either on its own or with alcohol, in a mixture called laudanum. These treatments were unreliable and had dangerous side effects. Once people began taking them, they could not stop, and so they became opium addicts.
Doctors looked for other substances that would stop people feeling pain, particularly during operations. The age of anaesthesia was born when ether became the first substance to be successfully used in surgery to stop the patient feeling pain. John Collins Warren was an American surgeon who, with an American dentist called William Morton, started using ether in 1846. He announced to his watching audience: “Gentlemen, this is no humbug.”
In 1899 aspirin became the first painkiller to be sold that people could use safely. It contained a mild chemical that came from the bark of the willow tree and was sold as “the wonder drug that works wonders”.
Throughout the 20th century, medical scientists developed many new painkillers. Some, such as morphine and related drugs, are like opium and work on the nerves in the brain to stop the sensation of pain. Paracetamol is a painkiller that also has an effect on the brain but is not addictive like opium. Other drugs, such as aspirin and ibuprofen, reduce the pain where the body has been damaged before the pain messages are sent along the nerves to the brain. Aspirin and ibuprofen also have the power to reduce swelling or inflammation.
WHICH DRUGS KILL BACTERIA?
Antibiotics are drugs that kill bacteria. They are very powerful weapons in the battle against bacterial infections, such as pneumonia. The world of medicine was changed forever when Alexander Fleming discovered penicillin, the first antibiotic, by chance in London in 1928.
Fleming was carrying out experiments on some bacteria, which he was growing in a small dish. The lid covering the dish was accidentally removed and the bacteria were contaminated with a fungus. Fleming was just about to throw the dish away when he noticed that some of the bacteria had been killed. His genius was to realize that the fungus was responsible.
Two chemists, Howard Florey and Ernst Chain, developed the antibiotic from the fungus, and convinced the world that it worked. During World War II, penicillin saved the lives of many thousands of soldiers, whose infected wounds would otherwise have killed them. Soon, doctors were equipped with a whole range of antibiotics, such as streptomycin for fighting tuberculosis.
RECREATIONAL DRUGS
Many people take a drug for a reason that is not medical. These drugs include legal ones, such as alcohol, nicotine, caffeine and tranquillizers, and illegal ones, such as cannabis, cocaine, heroin, ecstasy and amphetamines. Their reasons for starting to take one of these drugs may be because they are bored and want excitement. Sometimes people take the drugs because they are depressed and want to alter their feelings about the world. Perhaps someone offers them a drug and they cannot say “no” or they simply want to be part of a crowd.
People start to suffer problems when they take a lot of a drug or take it for a long time—they become addicted to a drug. They have a physical dependence when their bodies start to need the drug in order to carry on as usual. The drug users also have a psychological dependence when their mind and emotions also start to need the drug. When they stop taking the drug, they experience unpleasant symptoms, such as feeling sick, sweating, shaking, various aches and pains, anxiety and depression.
Did you know?
• Smoking 3 or 4 cannabis joints can be as bad for your lungs as smoking 20 cigarettes.
• In the UK, the maximum punishment for supplying illegal drugs is life in prison and a fine.
• A part of the brain called the pituitary gland creates a natural drug called endorphine, which can help to reduce pain. More endorphins are created when people smile.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
------------------------------------------------------------
Chapter 2: Living things in their environment
Every living plant or animal has a home in some part of the world. A habitat is the place where plants and animals live. It is more than a home; it is more like a neighbourhood. For an animal, a habitat includes all the land the animal needs to hunt, gather food, find shelter, find a mate and raise a family. Plants need certain soils and climates to grow. In many ways, that habitat is a plant or animal’s address. Ponds, streams, rock pools and moorland are habitats. A large area, such as a forest, is made up of many smaller habitats.
DIFFERENCES BETWEEN HABITATS
Many factors affect the growth of plants, including differences in climate, light intensity, air, water, soil and exposure to the wind. Animals eat plants and so the kinds of plants that grow in an area affect the animals that live there. The species of trees and shrubs that grow in a shady area are different from those that grow in bright sunlight. Pure air encourages growth, but polluted air slows or stops it. Less water creates a desert, while more water creates a marsh. Poor soil allows only a few plants to grow, whereas a fertile soil allows more plants to grow vigorously.
SPECIALIZED HABITATS
Every habitat has the right conditions for the plants and animals that live there. Most animals and plants are very specialized and can only survive in a certain kind of habitat. Earthworms, for example, have a thin, moist skin, through which they breathe. They can live only in moist soil. Animals that live in drier places, including scorpions and many beetles, have thick, hard skins to prevent them drying out. Penguins and polar bears are adapted in different ways to life in the bitterly cold and icy polar regions.
UNUSUAL HABITATS
A few animals have adapted in unusual ways to life in harsh conditions. Some fish that live in the ocean around Antarctica have evolved up to eight natural antifreeze substances in their blood and tissues. These substances stop ice crystals from forming and spreading, and allow these fish to survive in the extremely cold water. The macaque monkeys that live in high altitude forests in Japan are able to survive the cold, snowy winter by spending long periods sitting in hot-water springs.
MORE THAN ONE HABITAT
Some animals move from one habitat to another at different stages in their lives. The monarch butterflies of North America spend winter in southern California or Mexico. In spring thousands of them fly to the northern United States and Canada. Birds such as swallows, swifts, house martins and cuckoos spend the summer months in Britain, where they nest and rear their young. In the autumn they migrate to Africa to spend the winter. Even mosquitoes have two habitats. The larvae hatch from eggs in ponds, ditches, marshes and other areas of stagnant water. The adult mosquitoes spend their short lives in gardens, hedgerows, fields and woodlands.
COMPETITION
No two plant or animal species living in a habitat can have exactly the same foods, nest sites or other living conditions. If, for example, two species of birds live in the same habitat and feed on the same kinds of berries, one or other will either have to choose to eat a different kind of food, move somewhere else or die. Under a rotting log you might find ants, millipedes, centipedes, woodlice, slugs, snails, spiders and beetles of different kinds. Although they all live in the same habitat, they all have slightly different foods and require slightly different living conditions from the other animals with which they share the rotting log.
HABITAT DESTRUCTION
Many plant and animal species around the world are in danger of extinction. They include about 10 per cent of all the plant species in the world and many unusual, interesting or beautiful animals. These include tigers, leopards, rhinoceroses, giant pandas and elephants, as well as many smaller animals. Some of these plants and animals are in danger because of hunting or collecting, or because other animals introduced by humans have taken their place.
The biggest single reason for animals and plants becoming endangered is because their habitats are being destroyed. Forests are cleared for farmland, mining, roads, factories and other developments, and so the habitats of many forest animals and plants are destroyed. On a smaller scale, hedgerows are dug up to create larger fields, which endangers many birds, small mammals and insects. Many rivers and lakes are polluted, and marshes are drained, which has led to a drop in the numbers of otters, fish and many invertebrate animals.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
Video on Global Warming click here
------------------------------------------------------------
Chapter 3: States of Matter: Solids, Liquids and Gases
Look at all the things around you. Most of them are solid—the tables, walls, cars, trees, books and food. Some, such as lemonade, water, milk and orange juice, are liquid. You probably cannot see any gases, but they are there, too—in a fizzy drink, a light bulb, the fumes from a car and the air you breathe.
WHAT ARE SOLIDS, LIQUIDS & GASES?
Everything in the world is made up of solids, liquids and gases. These are known as the three states of matter. They are all substances that have mass and take up space because they have volume. All those things around you are made of matter, so are you, as are the Earth and stars in the sky.
Solids, liquids and gases are made of molecules, which contain one or more atoms. In a solid, the molecules are bound together so strongly that its shape usually stays the same. In a liquid, the molecules are more loosely connected so that the liquid flows easily but has a level surface. In a gas the molecules move randomly in any direction so that the gas has no shape.
CAN ONE CHANGE TO ANOTHER?
Temperature is very important in deciding whether a substance exists as a solid, liquid or a gas. Think about the normal temperatures of where you live. The temperature of the air may freeze water in winter but very rarely reaches 50 degrees Celsius in summer. This range of temperature means that the solids, liquids and gases in the world will not normally change from one state to another.
Water is one of the few things that we can see as a solid, a liquid and a gas in our everyday lives. Water turns into ice at its freezing point of 0 degrees Celsius and turns into steam at its boiling point of 100 degrees Celsius. These are temperatures that we can create in our homes—in the fridge and the kettle.
When a solid, liquid or a gas is exposed to very high or very low temperatures, it can change to another state. Raising the temperature of a solid to its melting point will turn it into a liquid. Iron, for example, is normally a solid but deep in the Earth’s crust it is so hot the iron is a molten liquid.
Lowering the temperature of a gas to its liquefaction point will turn it into a liquid. Oxygen, for example, is normally a gas, but scientists can lower its temperature to -183 degrees Celsius so that it can be turned into a liquid.
BUT CAN A GAS BECOME A SOLID?
Sometimes, a gas can be solidified. For example, carbon dioxide is normally a gas but it can be turned into a liquid by lowering its temperature. If its temperature is lowered even further, liquid carbon dioxide becomes a solid. This is called dry ice. When dry ice is exposed to the normal temperatures of the air, it turns from a solid into a gas without first becoming a liquid.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
Video on the Phases of Matter click here
More YouTube videos click here
------------------------------------------------------------
Muscles and Bones - Student Book pages 6 and 7
Video clips used during the lesson:
1. Muscles and Bones with skin all around click here
2. The Skeleton Dance click here
Drugs - Student Book pages 8-13
When you are ill, your parents probably give you some medicine to bring your temperature down or to take the pain away. When you have a bad infection, your doctor prescribes an antibiotic for you. The medicine and the antibiotic contain drugs that affect the way your body works or help you fight disease.
WHAT TYPES OF DRUGS ARE THERE?
A pharmacist’s shelves seem to be full of drugs. Some drugs can be bought by adults over the counter, but most need a doctor’s prescription. As well as painkillers and antibiotics there are drugs to help people sleep, tranquillizers to relieve anxiety, medicines to stop coughs, nasal drops to clear blocked sinuses, steroids to reduce inflammation and drugs to lower blood pressure. The list seems endless and it is easy to believe that there is a drug to help every health problem we have.
Modern drugs are made artificially by pharmaceutical companies. Each drug has a chemical name and a trade, or brand, name that belongs to the manufacturer. For example, paracetamol, or acetaminophen, is the chemical name of a painkilling drug and Panadol, which contains paracetamol, is one of the trade names you may find in a pharmacist.
WHICH DRUGS RELIEVE PAIN?
Until the 20th century, drugs for relieving aches and pains were usually made from plants. Opium from a type of poppy was widely used, either on its own or with alcohol, in a mixture called laudanum. These treatments were unreliable and had dangerous side effects. Once people began taking them, they could not stop, and so they became opium addicts.
Doctors looked for other substances that would stop people feeling pain, particularly during operations. The age of anaesthesia was born when ether became the first substance to be successfully used in surgery to stop the patient feeling pain. John Collins Warren was an American surgeon who, with an American dentist called William Morton, started using ether in 1846. He announced to his watching audience: “Gentlemen, this is no humbug.”
In 1899 aspirin became the first painkiller to be sold that people could use safely. It contained a mild chemical that came from the bark of the willow tree and was sold as “the wonder drug that works wonders”.
Throughout the 20th century, medical scientists developed many new painkillers. Some, such as morphine and related drugs, are like opium and work on the nerves in the brain to stop the sensation of pain. Paracetamol is a painkiller that also has an effect on the brain but is not addictive like opium. Other drugs, such as aspirin and ibuprofen, reduce the pain where the body has been damaged before the pain messages are sent along the nerves to the brain. Aspirin and ibuprofen also have the power to reduce swelling or inflammation.
WHICH DRUGS KILL BACTERIA?
Antibiotics are drugs that kill bacteria. They are very powerful weapons in the battle against bacterial infections, such as pneumonia. The world of medicine was changed forever when Alexander Fleming discovered penicillin, the first antibiotic, by chance in London in 1928.
Fleming was carrying out experiments on some bacteria, which he was growing in a small dish. The lid covering the dish was accidentally removed and the bacteria were contaminated with a fungus. Fleming was just about to throw the dish away when he noticed that some of the bacteria had been killed. His genius was to realize that the fungus was responsible.
Two chemists, Howard Florey and Ernst Chain, developed the antibiotic from the fungus, and convinced the world that it worked. During World War II, penicillin saved the lives of many thousands of soldiers, whose infected wounds would otherwise have killed them. Soon, doctors were equipped with a whole range of antibiotics, such as streptomycin for fighting tuberculosis.
RECREATIONAL DRUGS
Many people take a drug for a reason that is not medical. These drugs include legal ones, such as alcohol, nicotine, caffeine and tranquillizers, and illegal ones, such as cannabis, cocaine, heroin, ecstasy and amphetamines. Their reasons for starting to take one of these drugs may be because they are bored and want excitement. Sometimes people take the drugs because they are depressed and want to alter their feelings about the world. Perhaps someone offers them a drug and they cannot say “no” or they simply want to be part of a crowd.
People start to suffer problems when they take a lot of a drug or take it for a long time—they become addicted to a drug. They have a physical dependence when their bodies start to need the drug in order to carry on as usual. The drug users also have a psychological dependence when their mind and emotions also start to need the drug. When they stop taking the drug, they experience unpleasant symptoms, such as feeling sick, sweating, shaking, various aches and pains, anxiety and depression.
Did you know?
• Smoking 3 or 4 cannabis joints can be as bad for your lungs as smoking 20 cigarettes.
• In the UK, the maximum punishment for supplying illegal drugs is life in prison and a fine.
• A part of the brain called the pituitary gland creates a natural drug called endorphine, which can help to reduce pain. More endorphins are created when people smile.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
------------------------------------------------------------
Chapter 2: Living things in their environment
Every living plant or animal has a home in some part of the world. A habitat is the place where plants and animals live. It is more than a home; it is more like a neighbourhood. For an animal, a habitat includes all the land the animal needs to hunt, gather food, find shelter, find a mate and raise a family. Plants need certain soils and climates to grow. In many ways, that habitat is a plant or animal’s address. Ponds, streams, rock pools and moorland are habitats. A large area, such as a forest, is made up of many smaller habitats.
DIFFERENCES BETWEEN HABITATS
Many factors affect the growth of plants, including differences in climate, light intensity, air, water, soil and exposure to the wind. Animals eat plants and so the kinds of plants that grow in an area affect the animals that live there. The species of trees and shrubs that grow in a shady area are different from those that grow in bright sunlight. Pure air encourages growth, but polluted air slows or stops it. Less water creates a desert, while more water creates a marsh. Poor soil allows only a few plants to grow, whereas a fertile soil allows more plants to grow vigorously.
SPECIALIZED HABITATS
Every habitat has the right conditions for the plants and animals that live there. Most animals and plants are very specialized and can only survive in a certain kind of habitat. Earthworms, for example, have a thin, moist skin, through which they breathe. They can live only in moist soil. Animals that live in drier places, including scorpions and many beetles, have thick, hard skins to prevent them drying out. Penguins and polar bears are adapted in different ways to life in the bitterly cold and icy polar regions.
UNUSUAL HABITATS
A few animals have adapted in unusual ways to life in harsh conditions. Some fish that live in the ocean around Antarctica have evolved up to eight natural antifreeze substances in their blood and tissues. These substances stop ice crystals from forming and spreading, and allow these fish to survive in the extremely cold water. The macaque monkeys that live in high altitude forests in Japan are able to survive the cold, snowy winter by spending long periods sitting in hot-water springs.
MORE THAN ONE HABITAT
Some animals move from one habitat to another at different stages in their lives. The monarch butterflies of North America spend winter in southern California or Mexico. In spring thousands of them fly to the northern United States and Canada. Birds such as swallows, swifts, house martins and cuckoos spend the summer months in Britain, where they nest and rear their young. In the autumn they migrate to Africa to spend the winter. Even mosquitoes have two habitats. The larvae hatch from eggs in ponds, ditches, marshes and other areas of stagnant water. The adult mosquitoes spend their short lives in gardens, hedgerows, fields and woodlands.
COMPETITION
No two plant or animal species living in a habitat can have exactly the same foods, nest sites or other living conditions. If, for example, two species of birds live in the same habitat and feed on the same kinds of berries, one or other will either have to choose to eat a different kind of food, move somewhere else or die. Under a rotting log you might find ants, millipedes, centipedes, woodlice, slugs, snails, spiders and beetles of different kinds. Although they all live in the same habitat, they all have slightly different foods and require slightly different living conditions from the other animals with which they share the rotting log.
HABITAT DESTRUCTION
Many plant and animal species around the world are in danger of extinction. They include about 10 per cent of all the plant species in the world and many unusual, interesting or beautiful animals. These include tigers, leopards, rhinoceroses, giant pandas and elephants, as well as many smaller animals. Some of these plants and animals are in danger because of hunting or collecting, or because other animals introduced by humans have taken their place.
The biggest single reason for animals and plants becoming endangered is because their habitats are being destroyed. Forests are cleared for farmland, mining, roads, factories and other developments, and so the habitats of many forest animals and plants are destroyed. On a smaller scale, hedgerows are dug up to create larger fields, which endangers many birds, small mammals and insects. Many rivers and lakes are polluted, and marshes are drained, which has led to a drop in the numbers of otters, fish and many invertebrate animals.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
Video on Global Warming click here
------------------------------------------------------------
Chapter 3: States of Matter: Solids, Liquids and Gases
Look at all the things around you. Most of them are solid—the tables, walls, cars, trees, books and food. Some, such as lemonade, water, milk and orange juice, are liquid. You probably cannot see any gases, but they are there, too—in a fizzy drink, a light bulb, the fumes from a car and the air you breathe.
WHAT ARE SOLIDS, LIQUIDS & GASES?
Everything in the world is made up of solids, liquids and gases. These are known as the three states of matter. They are all substances that have mass and take up space because they have volume. All those things around you are made of matter, so are you, as are the Earth and stars in the sky.
Solids, liquids and gases are made of molecules, which contain one or more atoms. In a solid, the molecules are bound together so strongly that its shape usually stays the same. In a liquid, the molecules are more loosely connected so that the liquid flows easily but has a level surface. In a gas the molecules move randomly in any direction so that the gas has no shape.
CAN ONE CHANGE TO ANOTHER?
Temperature is very important in deciding whether a substance exists as a solid, liquid or a gas. Think about the normal temperatures of where you live. The temperature of the air may freeze water in winter but very rarely reaches 50 degrees Celsius in summer. This range of temperature means that the solids, liquids and gases in the world will not normally change from one state to another.
Water is one of the few things that we can see as a solid, a liquid and a gas in our everyday lives. Water turns into ice at its freezing point of 0 degrees Celsius and turns into steam at its boiling point of 100 degrees Celsius. These are temperatures that we can create in our homes—in the fridge and the kettle.
When a solid, liquid or a gas is exposed to very high or very low temperatures, it can change to another state. Raising the temperature of a solid to its melting point will turn it into a liquid. Iron, for example, is normally a solid but deep in the Earth’s crust it is so hot the iron is a molten liquid.
Lowering the temperature of a gas to its liquefaction point will turn it into a liquid. Oxygen, for example, is normally a gas, but scientists can lower its temperature to -183 degrees Celsius so that it can be turned into a liquid.
BUT CAN A GAS BECOME A SOLID?
Sometimes, a gas can be solidified. For example, carbon dioxide is normally a gas but it can be turned into a liquid by lowering its temperature. If its temperature is lowered even further, liquid carbon dioxide becomes a solid. This is called dry ice. When dry ice is exposed to the normal temperatures of the air, it turns from a solid into a gas without first becoming a liquid.
Microsoft ® Encarta ® Premium Suite 2005. © 1993-2004 Microsoft Corporation. All rights reserved.
Video on the Phases of Matter click here
More YouTube videos click here
------------------------------------------------------------
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