BIOLOGY: FORM ONE: Topic 2 - SAFETY IN OUR ENVIRONMENT

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TOPIC 1: SAFETY IN OUR ENVIRONMENT

First Aid

First Aid is an immediate help which is given to a sick or injured person before sending him/her to the hospital for further treatment.

FIRST AID KIT

Importance of First Aid

1. Saves life
2. Reduces fear of death
3. Brings hope and encouragement to the patient
4. Relieves the victim’s pain
5. Prevents the illness or injury from becoming worse
6. Helps a person to recover from shock
7. It shows spirit of helping each other.

Components of the First Aid Kit and their Uses

Identity components of the first aid kit and their uses

First Aid kit is a small box which is used to keep instruments and chemicals for First Aid. The first Aid kit should be placed in a safe and accessible place.

Components of the First Aid kit

• A pair of scissors
• Gauze
• Assorted bandages
• Adhesive plasters
• Cotton wool
• New razor blade
• Gentian violet (GV)
• Petroleum jelly or Vaseline
• Safety pins
• Iodine tincture or spirit
• Soap
• Anti-pain (pain killers) e.g. Panadol
• Sterilized forceps and pins
• Liniment
• A pair of tongs
• Antibiotic solution

Uses of the instruments and chemicals in the First Aid kit

• A pair of scissors:is used for cutting dressing materials such as gauze, bandages·
• Gauze:is used to cover the wound to prevent dirt and micro-organisms from entering.
• Assorted bandages: are used for securing an injured part in order to protect and support it.
• Adhesive plaster:are used for covering minor wounds/cuts and grazes·
• Cotton wool:is used for cleaning and drying wounds and applying medicine·
• New razor blade:used for cutting any flaps of skin when cleaning the wound.
• Gentian Violet (GV):is used as an antiseptic to clean wounds.
• Petroleum jelly or Vaseline:used for treatment of burns
• Safety pins:used for holding/securing bandages.
• Iodine tincture or spirit:used for cleaning wounds to reduce bleeding.
• Soap:is used for washing wounds, hands and medical facilities.
• Anti-pain (pain killers):used to reduce pain.
• Sterilized forceps and pins:are used for removing splinters and grit from wounds.
• Liniment:used to reduce muscle pains.
• A pair of tongs:used for holding pieces of bandages when cleaning the wounds.
• Antibiotic solution:is used for applying in the wounds for killing micro-organisms.

FIRST AIDER

The First Aider is a specialist who gives first aid.

Qualities of the first Aider

1. She/he should have ability to assess the problem and give immediate and appropriate help.
2. She/he must be able to act quickly, quietly, calmly
3. She/he should be sympathetic to the victim
4. She/he should be able to recognize dangerous signs and give immediate help for example detecting immediately if -breathing has stopped or is failing -there is severe bleeding-poisoning-fractures
5. She/he should be able to help the injured person without unnecessary movement

Precautions to be observed by the First Aider

The First Aider should keep himself/herself safe to avoid dangers from the patient. Some of the dangers that s/he may face include infection by pathogens such as viruses and bacteria.So they should:

• Wear protective gloves to avoid contact with blood
• Wear eye protection
• Wear masks and gowns.

First Aid can be rendered to the victims of

• Drowning
• Muscle cramps
• Bleeding
• Poisoning
• Hiccups
• Suffocation
• Bruises Fainting Burns Sprain Bone fracture Snake bite

Procedures of Giving First Aid to Various Victims

Outline procedures of giving first aid to various victims

SNAKE BITES

A poisonous snake has two fangs one on each side of the upper jaw. The fangs are as sharp as needles. At the root of the fang there is a poison gland. When the snake strikes, it jabs downwards hitting the skin with its fangs and releases a few drops of venom.

Venom is the poison of the snake The action of striking forces the poison out and injects into the victim’s skin.

Sign and symptoms

• Immediate pain and swelling after the bite
• The skin becomes purple One or two punctured points may be seen where the fangs passed through the skin

SCORPION BITE

Scorpions are armed with a single curved stinger in the tail. Through this, they inject powerful venom that may produce convulsions and temporary paralysis.

The affected area feels as though is had been burned with a hot spark

How to give first Aid to a victim of scorpion bite

1. Apply tourniquet
2. Put ice on the injured area to relieve pain and prevent spread of the poison
3. Treat for shock
4. Rush the person to the hospital

DOG BITE

When someone is bitten by a dog, keep the dog under observation to see whether it has rabies. Rabies is one of the worst diseases known. It is caused by a virus which is present in the saliva of the infected animal.

If the animal has rabies, it will become restless, excitable, refuse to eat and barking tone will change. Later the dog then starts barking excessively.

How to help a victim of dog bite

• Wash your hands well with soap and water
• Wash the wound thoroughly with soap and water to remove the animal’s saliva using running water.
• Cover the wound with clean gauze.
• Bandage it carefully
• Take the victim to the hospital.

INSECT BITES

1. Spider bites : Some spiders have a harmless venom to man. But the black spiders can be dangerous to man. The injured person becomes weak and dizzy, feels nauseated and the muscles of the stomach may become hard especially in children.
2. Black and fire ants, bees : When a person has been stung by e.g. bees, severe pains are felt immediately.The person may be shocked, itching and swelling may follow.

A victim of spider bite can be helped by sending him/her to the hospital.

How to help

• Remove the insect’s sting
• Apply household ammonia and ice cubes
• Treat for shock

CHOCKING

Choking is caused when food or a foreign object becomes lodged in the windpipe.

Have you ever been with a person who is chocking? Did you know what to do?

When you are with a person that is chocking, first notice if person can talk, breath or cough. If so stay with that person until the air way is cleared by coughing.

Caution: Do not try to slap the person on the back. The slapping may cause the food to become more deeply ledged in the wind pipe.

If a person cannot talk or cough and appears to have a difficult in breathing, apply quick abdominal thrusts i.e. Heimlich maneuver as follows;

• First stand behind the chocking victim
• Put your arms around the person, placing your firsts just below the breast bone as shown above.
• Give a series of quick, sharp upward and inward thrusts

These thrusts push in on the diaphragm and the thoracic cavity suddenly decreasing its volume.

Air pressure is exerted below the obstruction which projects it forcefully from the windpipe.

POISONING

A poison is any substance which can loss of one’s life or seriously endanger health when taken into the body.

In every household there are different kinds of things which are poisonous. Some are deadly even on a very small dose. Others may be more or less harmless when taken in small quantities.

Examples of poisonous substances at home are kerosene, disinfectants, paints, medicines, artificial fertilizers, etc.

First aid to poisoning

• Look for the poison
• Identify the poison
• Neutralize the poison by giving the victim plenty of milk to drink or egg white or water.
• Induce vomiting if the poison is not strong acid or alkali as these are corrosive substance.
• If the problem is severe, rush him or her to the hospital.

BONE FRACTURE

A person with a bone fracture experience the following;

• Severe pain around the injured part
• Lack of movement
• Swelling
• Fainting or shock

How to help

• Treat for a shock
• Keep the patient absolutely quite
• Prevent further damage to injured part by using a splint.

BONE DISLOCATIONS

These are bones which have come out of place at a joint.

How to help

• Bring the bone back into fixed position
• Bandage it firmly in place so that it does not slip out again

SHOCK

Shock is a sudden violent disturbance of the mind or emotion

Causes of shock

1. Bad news
2. Severe illness
3. Heavy bleeding
4. Dehydration
5. Severe burns
6. Accident

Ways of preventing shock

• Lie down the person with his feet higher than his head
• Loosen the belt and shoes
• If the person is conscious give him some tea or any soft drink.
• Treat his/her wounds if any
• Stop any bleeding Keep the person warm if he/she feels cold

ELECTRIC SHOCK

How to help

• Switch off the electricity immediately
• If not possible to switch off the electricity, take the victim away from the source of electricity using a dry wooden material or rope.
• Loosen any tight clothes
• If the person is unconscious, apply mouth to mouth respiration
• Treat for shock
• Take the person to the hospital immediately

BRUISES

A bruise is an injury beneath the skin. Bruises can be identified by pain, swelling or a mark under the skin.

How to treat bruises

• Wash your hands using water and soap
• Wash the bruised part
• Apply cold clothes or ice immediately to reduce pain and swelling
• If swelling continues take the victim to the hospital

VOMITING

Vomiting is an involuntary ejection of substance from the stomach through the mouth.

Possible causes of vomiting

1. Allergic reactions
2. Diseases e.g. malaria
3. Physiological condition e.g. pregnancy
4. Food poisoning
5. Unpleasant smell or taste
6. Drinking a lot of water when thirsty.

How to help

• Give the person a rehydration drink or oral rehydration salts solution.
• Allow the person to have a complete rest
• If vomiting continues, take the patient to the hospital.

MUSCLE CRAMPS

Muscle cramps occur as a result of uncontrolled muscle spasms and contraction.

How to help

• Lay the victim down
• Massage the cramped area gently
• Apply some anti-cramp ointment to the affected area
• If the problem persists seek for a medical help

Muscle cramp can cause;

• Severe pain
• Loss of movement

DROWNING

Drowning is a situation where someone has stopped breathing due excessive drinking of water following sinking into water.

Offering first aid to a drowned victim

• Lay the person on his back and tilt his head backwards so that his mouth falls forward
• Pull the tongue forward.Use a dry cloth to hold the tongue.
• Hold his nose close with your fingers
• Carry out mouth to mouth breathing by blowing gently into the person’s mouth about 30 times a minute but do not blow too hard.This process is called artificial respiration.
• Keep the person warm.

FAINTING

Fainting is caused by a temporary fall in the blood supply to the brain, sometimes brought on by emotional shock or prolonged standing.

How to help

• Keep the victim lying down with his/her legs raised in order to maintain blood pressure in the brain.
• Do not try to warm the victim.
• Loosen any tight clothing around the neck, chest and waist.
• Supply the patient with plenty of fresh air by fanning or mouth to mouth respiration.
• If there is no improvement rush the victim to the hospital.

BLEEDING

How to help the victim

(a) Severe cuts

• Severe bleeding with blood flowing out rapidly must be stopped at once by pressing with fingers directly on the wound or pressing the edges of the wound together.
• Lay the victim down.
• If the wound is in a limb raise it provided it is not fractured.
• When the bleeding has slowed down press a pad of material over the wound and tie it rapidly in place.
• If blood oozes through, apply more material on top of the original pad.

(b) Simple cuts

• Wash your hands well by using soap and water
• Wash the wound
• Cover the wound with clean dressing dipped in iodine solution and bandage the wound

(c) Nose bleeding Bleeding usually occurs near the tip of the nose. The bleeding may be a result of diseases such as

• High blood pressure
• Rheumatic fever Or
• Injury

Nose bleeding is also likely to occur at high altitude as a result of cold.

A nose bleeding victim

How to help

• Let the victim sit quiet. This makes the heart beat to slow down and hence reduces bleeding.
• Let the victim lean the head slightly backward or make him/ her lie down on his/ her back.
• Press on the side of the nose where the blood is flowing for about 10 minutes.
• Allow the victim to breath through the mouth
• Apply cold, wet compression over the nose and face. If this does not work take the victim to the hospital

The right position to offer first aid to a nose bleeding victim

BURNS AND SCALDS

A burn is caused by dry heat e.g. flame of hot object. A scald is caused by a steam or boiling water. The treatment is the same for both burns and scalds except that in scalds any wet clothing should be carefully removed while in burns clothing should be left in place. If clothes are burning cover the victim with a heavy blanket to cut off the air supply.

Dip the burning limb into clean cold water or press the affected area gently with an ice block. Do not break the blisters. Cover the injured area with clean dry cloth to keep away bacteria entering the damaged tissue. If the situation is serious take the victim to the hospital immediately.

CHEMICAL BURNS (ACIDS AND ALKALIS)

How to help

• Strip off all clothing which has been contaminated by the chemical.
• Wash the affected area with plenty of water.
• Apply moist packs soaked in a weak solution of baking soda.
• Vinegar can be used for alkaline burns.

HICCUPS

Hiccups is due to involuntary contraction of the respiratory muscle, giving a characteristic sound

How to help

• Pulling out the tongue
• The victim may swallow finely crushed ice
• Holding a breath for a long time may also help
• Children can be given a teaspoonful of a weak solution of sodium bicarbonate or lemon juice.

Safety at Home and School

Common Accidents at Home and School

Mention common accidents at home and school

What is an accident?

An accident is something unexpected that may cause injury and sometimes lead to death. Accidents may be difficult to predict and prevent.

Below is a list of some common accidents at home and school:

• Bites e.g. snake bite, insect bite, scorpion bite and dog bite.
• Burns caused by hot liquids, cooking pot, lamps, hot food, steam, burning wood, charcoals and those caused by corrosive chemicals such as concentrated acids and strong alkalis.
• Falls, e.g. wall falls, tree falls, bed falling, etc.
• Cuts and scratches caused by knives, hoes, razor blades and other sharp objects.
• Choking caused by drinks, food or objects
• Electric shock due to unguarded electric outlets and lightning.
• Poisoning caused by taking chemicals and excessive intake of medicines.
• Foreign bodies in the eye, ear and nose
• Drowning which may occur in very small amount of water such as baths, ponds, pit latrines, wells and water tanks.
• Nose bleeding, bruises, suffocation, fainting etc.

Home environment

A child crawling towards boiling water

Ways of Maintain Safety at Home and School

Explain ways of maintain safety at home and school

Ways of preventing accidents at home and school include the following:

• Medicines and potential poisonous chemicals should be kept out of reach of children.
• Children should be monitored closely when playing.
• Sharp objects like broken bottles, razor blades and laboratory equipments should be well disposed of.
• Laboratory chemicals should be labelled and if possible appropriate warning signs should be indicated.
• One should not take medicine unless prescribed by the doctor.
• Bushes and tall grasses around the house should be cut to avoid harbouring snakes, bees and other dangerous animals.
• Students should observe and adhere to laboratory rules.
• Walls and trees that are at a risk of falling should be dismantled or cut down respectively.
• Flammable substances should be properly kept.
• Pits dug around the house should be buried. Pools should be drained if possible and all water storage containers should be properly covered.
• Avoid using charcoal to warm oneself during night when sleeping as continued inhalation of carbon monoxide from the charcoal may lead to death
• Burning candles should be put off when sleeping.
• Players should adhere to game rules.
• Laboratory doors should open outwards for easy exit in case of fire. Emergence door is also necessary for this case.
• Equipment like hoes, axes and knives should be properly kept
• Turn off all the gas taps after experiment.

Ways of maintaining peace and safety at home and school

• Avoid risk behaviours such as playing near deep ponds, playing with knives, alcoholism etc.
• Dangerous things such as drugs should be kept away from children’s reach
• Report any dangerous event that someone engages in.
• Be positive and supportive to each other.
• Social problems occurring at home or school should be solved keenly.
• One should be good to him/herself.
• Parents should give their children education on how to live and interact with others.

Waste Disposal

The Terms “Waste” and Waste Disposal

Explain the terms “Waste” and waste disposal

What is waste?

Waste can be defined as unwanted materials or substances that are left after you have used something. Waste materials or substances are unwanted because the good part of them has been removed or it is not used.

Types of Waste

Identify types of waste

According to physical state, wastes can be classified as;

1. Solid wastes
2. Sludge wastes
3. Liquid wastes
4. Gaseous wastes

Solid wastes

These are wastes which comprise of about 73% of the solid wastes. Example of solid wastes include house hold solid wastes such as vegetable, fruit and garden wastes, papers, cans, plastics, bread wrappers, broken glassware, batteries from watches, radios, mobile phones, etc. and junked automobiles.

Industrial solid wastes

These types of wastes include packaging materials, metal turnings, scrappers, plastics and junked automobiles.

Medical solid wastes

These include packaging, used syringes and soiled dressings.

Market, yard and street sweepings

These are wastes such as paper, glass, cans, plastics, and vegetable wastes.

Sludge wastes

These are semi-solid wastes i.e. wastes which are neither solids nor liquids, for example, a mixture of livestock urine and cow dung.

Liquid wastes

These are wastes which are in the form of liquid or watery materials. They contain less than 25% solid substances. Example of liquid wastes include water from sinks, wash basins and baths, urine, industrial effluent, oil spills and agricultural chemicals e.g. insecticides and pesticides.

Gaseous wastes

These are waste materials which are released into the atmosphere in gaseous state. Examples of gaseous wastes are carbon dioxide, carbon monoxide, sulphur dioxide and nitrogen dioxide.

Most of the gaseous wastes come from industries and automobile exhaust fumes, laboratories and burning of organic materials such as plastics and polythene bags.

Wastes can also be classified as

1. Hazardous waste
2. Non- hazardous wastes

Hazardous wastes: These are harmful wastes which can endanger the health of living organisms. Examples of hazardous wastes include paints, engine oil, car batteries, used syringes, soiled dressings, organochlorides, radioactive elements and heavy metals e.g. lead and mercury.

Non hazardous wastes: These are wastes which are not harmful in that they do not endanger the health of living organisms. Examples of such wastes include packing materials, papers, plastics, cans, water from wash basins, baths, etc, vegetable, fruit and garden wastes and glass.

Furthermore, wastes can also be classified as;

1. Recycled wastes
2. Non- recycled wastes

Recycled wastes

These are wastes which can be used to manufacture new products. The used materials are recycled instead of being thrown away. Examples of waste materials which can be recycled include metals, glass, papers, cow dung, beer bottles and plastic bags.

Non- recycled wastes

These are wastes which cannot be used to manufacture new products and cannot be used again e.g. soiled papers and cotton wool.

Wastes ready for disposal

Waste Disposal

Waste disposal is the process of getting rid of waste materials that people generate or the act of getting rid of unwanted materials and items of no value or in excess.

Basic Principle of Waste Disposal

Outline basic principle of waste disposal

Principles of waste disposal

1. Recyclable wastes should be separated from non- recyclable wastes
2. Greater precaution should be observed when disposing hazardous wastes and it is important to separate them from other garbage
3. It is important to use protective materials e.g. gloves when collecting and disposing wastes.
4. Food and yard wastes should be separated from other garbage so as to be delivered to a compost site
5. It is necessary to treat sewage before it is empted into the water bodies
6. Sewage systems should be checked from time to time to control leakages
7. Radioactive wastes should be disposed off by putting them in tanks and dipping them in deep oceans.

Proper Ways of Disposing Waste

Demonstrate proper ways of disposing waste

Methods of waste disposal

Most cities and towns have waste collecting departments or private firms that gather municipal solid wastes from homes and other buildings.

Incineration

This is the method which involves burning of waste products at high temperatures.

Land disposal

This involves hauling garbage to an area owned by a community or a private firm. Land disposal may range from unsanitary open dumps to sanitary landfills.

Unsanitary open dumps are poor methods of waste disposal because they cause environmental problems such as:

• May produce bad odors
• Ruin the area’s appearance
• Rain water drains through refuse and carry harmful substances to nearby streams and to water used for drinking.
• Decomposing wastes produce flammable gas called methane and methane explosions may result.

Wastes disposed near community water source

Sanitary land fills are intended to protect the environment. The waste is packed firmly by tractors and covered with specially manufactured materials. The covering is done in order to limit blowing papers, odors, fires and run off of polluted water.

Note: A secure sanitary land fill is lined with materials that prevent water from carrying leachates (dissolved substances) from the refuse into underground water supplies.

Waste bin collection

This is intended to collect smaller quantities of wastes. The waste bins are placed along the corridors or in every room or house which in turn is emptied into big waste bins.

Sewage system

Sewage is water that contains waste matter produced by human beings. It is also called waste water. Sewage comes from toilets and sinks of homes, restaurants, office buildings and factories Sewage system involves the use of collection pipes or pit latrines where the sewage is periodically removed and transported to a sewage works where it is treated to make it harmless.

Recycling

Recycling is the process of reusing the materials instead of throwing them away. The waste products are used to manufacture the same or different products such as:

• Cardboard or cow dung can be used to generate Biogas.
• Thermoplastics can be melted and remoulded.
• Organic wastes produced domestically or commercially can be composted.
• Kitchen refuse can be used to feed animals such as dogs, pigs, cattle, etc.
• Newspapers, magazines cartons and packing materials can be used to manufacture tissue papers.
• In Tanzania coffee husks are converted into a form of charcoal which is used for cooking
• Coconut and agricultural wastes can be converted into papers.
• Jute wastes can be converted into hard boards.
• Sewage and factory wastes can be purified to an extent that can be pumped into storage tanks and used for all domestic purposes.
• Glass bottles can be used for storing specimens or medicines.

Waste generation reduction

Waste reduction is deliberate effort to produce fewer wastes. For example, people can reduce waste by buying items that can last longer or have less packing.

Effects of Poor Waste Disposal

Explain effects of poor waste disposal

The following are some of the effects of poor waste disposal;

• Produce bad odors
• Ruin the areas appearance
• Decomposing wastes produce flammable gas called methane and this may result to explosion of the gas which may cause a loss of material property and human life.
• Rain water drains through refuse and carry harmful substances to nearby streams and water used for drinking which may later lead to eruption of diseases like cholera and may kill organisms found in water
• Poor disposal of clinical wastes on land fill site may encourage bacterial breeding leading to possible infections in the area
• Unregulated dumps where waste is burned in the open can cause smoke and foul smelling air.
• Burning may also result into production of air pollutants which may affect the ozone layer and possible cause of respiratory diseases.

The Concept of Health and Immunity

The Concepts of Health and Immunity

Explain the concepts of health and immunity

Health is a state of physical, mental and social wellbeing. It involves more than just the absence of disease. A truly health person not only feels good physically but also has a realistic outlook on life and gets along well with other people.

Elements of physical health

• Nutrition:Balanced diet provides all the food substances needed by the body for health growth and development.
• Exercise:Exercises help to keep the body healthy and fit. Vigorous exercises strengthen muscles and improve the function of the circulatory and respiratory system.Physical fitness benefits both physical and mental health and helps the body to withstand stress.
• Rest and sleep:Help to overcome fatigue and restore energy to the body. Everyone needs rest and sleepRest and relaxation are as important as sleep. After strenuous work or exercise a person may need a period of total rest.
• Cleanliness:Cleanliness prevents the growth of bacteria and other germs that can cause diseases. A regular bath or shower keeps the body free from dirt and odour. It also helps to prevent skin infections.
• Medical and dental care:Regular check ups by dentist and physician play an important role in safeguarding health. Doctors recommend that people seek medical care at first sign of illness. Early care can result in quicker cure and lower medical costs.
• Avoiding risk behaviours:Careful observation over a range of life style factors indicate that positive changes can bring about corresponding change in health status Risk behaviours that need to be avoided include: Smoking: cigarette smoking increases respiratory diseases such as bronchitis and increases risk of death from lung cancer and heart attack; Alcoholism: heavy, long term drinking has several effects on the body. It affects nervous system, cause liver disease (cirrhosis), etc; Drug abuse: drugs can cause addiction, long term harmful effects, disruption of normal life and some can lead to death.

MENTAL HEALTH

Mental health is as important as physical health and to a great extend depends on it.

Elements of mental health

Emotional development

Experiences during childhood strongly influence a person’s mental health throughout life. Children remain dependent for many years. At this period they learn certain guidelines for relating to other people. Thus children develop the knowledge necessary to deal with difficult situations in life. This knowledge helps them maintain good mental health throughout life.

Emotional development does not end when a person reaches adulthood. An individual's mental health continues to change from time to time. These changes result from daily circumstances that cause either pleasure or pain to the person.

Handling stress

Stress handling is essential for avoiding both mental and physical illness. Feelings of stress are the body’s response to any threatening or unfamiliar situation. Causes of stresses include the following:

• Most severe stress may result from divorce or loss of job.
• Stress can also occur even in pleasant situations such as: Watching a football game, Waiting for a lovely one to return from a trip, etc.

If not handled properly stress can lead to

• Physical or emotional illness
• High blood pressure
• Stomach ulcers

No one can avoid stress but certain things that can be done to lessen it include:

• Regular exercises and sufficient sleep strengthens the body resistance to stress
• Relax by resting
• Taking a walk
• Meditating
• Working with hobby

Social relationships

Close personal relationships with friends and relatives provide opportunities for communication, sharing and emotional growth.Such relationships also provide strength and support for dealing with challenging situations or personal problems.

Importance of good health

1. Enables people to enjoy life and have opportunity to achieve their goals.
2. Sets someone free from attack by diseases.
3. Enables people to work effectively and efficiently.
4. Good health helps people to participate in social issues.
5. Enables mothers to deliver healthy babies.
6. Raises the family economy which in turn ensures peace and security within the family and the surrounding community.

Types of Body Immunity and Their Importance

Mention types of body immunity and their importance

Immunity is the ability of the body to resist certain diseases and poisons. Immunity can also be defined as the ability of the body to defend itself against infectious agents, foreign cells and even abnormal cells such as cancer cells

The scientific study of immune system is called immunology.

Immune system

The immune system comprises of a group of cells, molecules and tissues that help defend against disease and other harmful invaders.

The invaders include disease-causing organisms (pathogens) such as bacteria, fungi, protozoa, virus and worms. A key feature of immune system is its ability to destroy foreign organisms, leaving the body’s own health tissues alone.

The immune system consists of white blood cells, lymph nodes, spleen, liver and bone marrow.

Types of immunity

Basically there are two types of immunity

1. Natural immunity
2. Artificial immunity

Natural immunity

Natural immunity is that which an individual is born with. Natural immunity can be divided into categories, namely:

1. Natural active immunity
2. Natural passive immunity

• Natural active immunity:This immunity develops in a body after a natural infection. After infection, antibodies are produced in the body. The antibodies normally reside in the blood or in other parts of the body. The body can make more antibodies whenever the pathogen tries to attack the body again.
• Natural passive immunity:This type of immunity is achieved during development of the foetus where antibodies pass from the mother to the foetus through placenta or through the mother’s milk after the baby is born. The antibodies disappear from the infant a few months after birth.

Artificial immunity

Artificial immunity is that which an individual acquires during his/her life time.

There are two types of artificial immunity

1. Artificial active immunity
2. Artificial passive immunity

Artificial active immunity

This is immunity introduced in the body by immunization. Immunization is the process of introducing a vaccine into the body of an animal in order to increase its ability to produce antibodies. These antibodies protect the person if he/she is exposed to the actual disease.

• Most vaccines contain disease-causing bacteria or viruses that have been killed.
• Others consist of the live germs but in a weakened form or attenuated.
• Toxoid vaccines are made from poisons produced by disease-causing organisms.
• These poisons are chemically treated so that they provide immunity without causing disease.
• Some vaccines are made from parts of disease-causing organisms.

Vaccines have been developed against many diseases such as chicken pox, diphtheria, influenza, measles, meningitis, mumps, pneumonia, poliomyelitis, cholera, rabies, rubella (German measles), tetanus, whooping cough and yellow fever.Vaccines can be taken through, injection, rubbing or the mouth (orally).

Artificial passive immunity

This type of immunity involves the injection of serum into the body of an organism. Serum contains antibodies that have been formed in another person or animal. It provides immediate protection from infection and lasts for weeks or months and after that period there are no antibodies left in the body and therefore no immunity.

Factors which Affects Body Immunity

State factors which affects body immunity

Factors which may lead to low of body immunity

1. Alcohol and other toxic drugs.
2. Lack of immunisation.
3. Lack of proper balanced diet.
4. Inability of the body to produce antibodies and white blood cells.
5. Pathogens of HIV (Human Immunodeficiency Virus)

Personal Hygiene and Good Manners

Concepts of Personal Hygiene and Good Manners

Explain concepts of personal hygiene and good manners

Personal hygiene refers to individual cleanliness. It mirrors on how one takes care of oneself.

Good manners refer to acceptable person’s ways of behaving towards others.

Principle of Personal Hygiene and Good Manners

Outline principle of personal hygiene and good manners

Principles of personal hygiene

• Eating balanced diet regularly to maintain good health
• The body should be washed daily and hair combed regularly
• Teeth should be brushed after every meal
• The nails should be cut short
• Wear clean and ironed clothes
• Avoid risk behaviours like smoking cigarettes, drinking alcohol, prostitution and others
• Wash your hands with soap before and after meals and after visiting a lavatory
• Have enough sleep and rest.
• Take regular exercises to maintain fitness
• Underwears should be changed regularly
• Bedding should be changed regularly

Principles of good manners

1. Respect – an individual should have good respect such as: showing great respect to elders by helping and greeting them decently; being polite and humble; and talking in a clear and calm voice.
2. Tidiness – every body should look smart all the time. An individual should: keep the bedroom neat; brush shoes; wear clean and ironed clothes; cut nails and hairs short; comb or plait the hair nicely, etc.
3. Discipline – an individual should be well disciplined e.g. avoid using bad language; cover, your mouth when sneezing, yawning or coughing; and portray good postures e.g. sitting properly in class and at home.
4. Good eating habits (table manners) which include the following: Eating at regular time intervals; Avoid talking with food is in the mouth; Do not pile food up on your plate. Serve yourself with a reasonable amount while considering others; In case the food given is not good, make an excuse that you are not hungry or not feeling well rather than showing or saying that the food is not good; Don’t tell stories that will make others laugh when eating; Always wash your hands before and after eating
5. Putting things in proper order: All objects in the surrounding should be kept properly and in a right place e.g.: Rubbish should be disposed as required; Books should be kept in shelves; Cooking and eating utensils should be kept well in the cupboards; Clothes should be properly ironed, folded and kept.

Requirements of Personal Hygiene and Good Manners

Mention requirements of personal hygiene and good manners

Requirements of personal hygiene and good manners include towel, soap, comb, brush, basin, toothbrush, a pair of scissors, razor blades, water and cosmetics.

Ways of Maintaining Proper Personal Hygiene During Puberty

Outline ways of maintaining proper personal hygiene during puberty

Puberty is the adolescent period. It is the period when one experiences physiological changes in the body. The physiological changes mark the beginning of adolescence.Puberty begins the age of 10 to 12 years for girls and 11 to 14 years for boys.

Ways of maintaining proper hygiene during puberty

1. Both sexes should wash their bodies regularly
2. During menstruation, girls should use good quality sanitary towels or pads and change them as necessary.
3. Boys should undergo circumcision and females should avoid female genital mutilation
4. Underwears should be washed and changed regularly
5. Both boys and girls should avoid irresponsible sexual behaviours such as prostitution and rape so as to keep away from sexually transmitted diseases (STDs)
6. Hair in the armpits or pubic areas should be shaved or trimmed.

The Importance of Personal Hygiene and Good Manners

Explain the importance of personal hygiene and good manners

Importance of personal hygiene and good manners include:

1. Reduces chances of pathogen infection
2. Enhances social acceptance in the society
3. Prevents one from getting choked while eating
4. Maintains natural body state
5. Maintains personality of an individual in the society
6. One becomes respected by others
7. Maintains health of the body and mind

Infections and Diseases

The Meaning of the Terms Infection and Disease

Explain the meaning of the terms infection and disease

Infection is the invasion of disease-causing micro-organisms into the body. Disease is the disturbance of the normal state of the body. It is a disordered state of an organ or organism. Infections normally lead to diseases.

Classification of diseases

Diseases are classified as:

1. Infectious (communicable) diseases
2. Non-infectious (non-communicable) diseases

Infectious (communicable) diseases

These are diseases which can be transmitted from one person to another person. Communicable diseases are normally caused by micro- organisms like viruses, bacteria, fungi and protozoa, etc

Examples of infectious diseases include: malaria, typhoid, tuberculosis, cholera, gonorrhoea, syphilis, ebola, AIDS, chlamydia, etc.

Many of the infectious diseases are transmitted by a way of:

• Droplet of liquid
• Air
• Food or water
• Sexual intercourse
• Touch or contact e.g. ringworm
• An intermediate organism called a vector e.g. malaria by mosquito and bubonic plague by rat flea.

Diseases causing micro-organisms can enter the body through mouth, nose, skin, vagina, anus, penis, ears, eyes and open wounds.

Infectious diseases can be:

1. Epidemic disease - a disease that affects a larger number of people in a short period of time in a region for example, cholera, meningitis, bubonic plague, rift valley fever (RVF), tuberculosis, etc.
2. Pandemic disease - a communicable disease which is wide spread over a country continent or the whole world, for example HIV/AIDS, etc.
3. Endemic disease - a communicable disease which occurs in an area continuously for example, bilharzia, sexually transmitted diseases (STDs), malaria (an endemic disease in tropical regions) and cholera (endemic in Asia).

Non- infectious (non-communicable) diseases

These are diseases which can not be transmitted from one person to another. Examples of non-communicable diseases include:

Environmental diseases e.g.:

1. Lung cancer
2. Asbestosis
3. Asthma
4. Coronary (heart) diseases
5. Alcoholism

Deficiency diseases

These diseases are due to lack of certain nutrients in the diet. They may be due to lack of one of the main food groups e.g.:

1. Kwashiorkor: lack of protein
2. Marasmus: lack of both carbohydrate and proteins
3. Night blindness: lack of Vitamin A
4. Beriberi: lack of Vitamin B₁
5. Scurvy: lack of Vitamin C
6. Rickets: lack of Vitamin D, calcium, and phosphorous
7. Anaemia: lack of iron
8. Goitre: lack of iodine
9. Excessive bleeding (haemophilia): lack of Vitamin K

Genetic and congenital disorders e.g.

1. Colour blindness
2. Haemophilia
3. Sickle cell anaemia
4. Albinism
5. Down’s syndrome
6. Klinefelter’s syndrome
7. Turner's syndrome

Ageing and degenerative diseases e.g.

1. Long sightedness due to weakening of eye muscles
2. Arteriosclerosis (hardening of arteries)
3. Arthritis – ageing of joint and bone tissues

Mental illness e.g.

1. Schizophrenia
2. Senile dementia
3. Depression

Hormonal diseases e.g.

1. Diabetes mellitus
2. Diabetes inspidus
3. Cretinism

Common Infections and Diseases

Mention common infections and diseases

Common Infections and Diseases include the following:

1. CHOLERA
2. MALARIA
3. TYPHOID
4. TUBERCULOSIS (T.B)
5. MENINGITIS
6. AMOEBIC DYSENTRY (AMOBIASIS)
7. PLAGUE
8. TRYPANOSOMIASIS (SLEEPING SICKNESS)
9. BILHARZIA (SCHISTOSOMIASIS)
10. ATHLETE’S FOOT
11. GONORRHOEA
12. SYPHILIS
13. CLAMYDIA
14. GENITAL HERPES
15. GENITAL WARTS
16. HEPATITIS B
17. TRICHOMONIASIS
18. CANDIDIASISTest Yourself

The Causes, Symptoms, Mode of Transmission and Effects of Common Infections and Diseases

Explain the causes, symptoms, mode of transmission and effects of common infections and diseases

CHOLERA

Cause: It is caused by a bacterium known as Vibrio cholerae

Symptoms

1. Severe watery diarrhoea and vomiting
2. Body weakness
3. Fast and weak pulse
4. Low blood pressure
5. Wrinkled skin and sunken eyes due to dehydration
6. Rapid loss of weight

Transmission

Cholera is transmitted through:

1. Food or water borne material contaminated with faeces from infected person
2. Handling of contaminated objects
3. Vectors e.g. flies moving from human faeces to food.

MALARIA

Cause:Malaria is caused by a protozoan called plasmodium.

Signs and symptoms

1. High fever. Fever may be continuous, irregular or twice daily.
2. Vomiting
3. Lack of appetite
4. General body weakness
5. Joint pains

Transmission

Malaria is transmitted by a female anopheles mosquito. The mosquito sucks blood containing plasmodium from the infected person and introduces them into the body of a health person. In rare cases malaria can be transmitted through blood transfusion from the infected person to a health person.

TYPHOID

Cause: It is caused by a bacterium known as Salmonella typhus. The bacteria damage the intestinal wall and other parts of the body like gall bladder, spleen and bone marrow.

Signs and symptoms

1. Mild fever
2. Slight abdominal pains
3. Diarrhoea
4. Vomiting
5. Ulceration and rupture of intestine

Transmission

The disease is spread through

1. Contaminated water and food
2. Handling of contaminated objects
3. Vectors of the disease e.g. houseflies

TUBERCULOSIS (T.B)

Cause: T.B is caused by bacterium called Mycobacterium tuberculosis. The bacteria can attack the lungs or any part of the body and destroy tissues.

Signs and symptoms

1. Loss of weight
2. Coughing
3. Fever
4. Chest pain
5. Blood in the sputum

Transmission

1. Through droplet infection
2. Through drinking milk from infected cattle
3. T.B is common in overcrowded areas with poor sanitation

Appropriate Preventive and Control Measures for Common Infections and Diseases

Suggest appropriate preventive and control measures for common infections and diseases

Prevention of Cholera

1. Wash hands after visiting toilet or latrine
2. Food should be well cooked and drinking water should be boiled and well filtered
3. Hands should be washed before and after eating
4. Food should be well covered
5. Utensils should be washed thoroughly
6. Maintain general environmental cleanliness

Control of Cholera

1. The infected person should be isolated
2. Special precautions should be taken when handling the infected person
3. Vaccination is possible

Treatment

1. The disease can be treated by using antibiotics such as tetracycline, chloramphenicol
2. Administering rehydration salt solutions

Effects

1. May lead to death
2. Extra medical expenses
3. Failure to perform daily activities

Prevention and control of malaria

1. Spraying insecticides to destroy adult mosquitoes
2. Introducing fish eating mosquito into stagnant water e.g. Gambusia that feed on mosquito larvae.
3. Draining stagnant water to remove the breeding sites for mosquitoes
4. Use of mosquito nets to prevent mosquitoes from biting people
5. Screening the windows with mosquito-proof wire-mesh to prevent entry of mosquitoes in the house through the windows.
6. Wear long-sleeved shirts and trousers to prevent mosquito bites.
7. Mosquito larvae and pupa can be killed by spraying oil into stagnant water that cannot be drained.
8. Taking regular weekly doses of preventive drugs to kill parasites on entry.
9. Cutting bushes around the houses to destroy shelter for mosquitoes
10. Using mosquito repellents to flee away the mosquitoes

Treatment

Anti-malarial drugs can be used to treat the disease e.g. quinine, fansider, mefloquine, chloroquine, etc.

Effects

1. Can cause death
2. Can lead to mental confusion in case of cerebral malaria
3. Paralysis and unconsciousness
4. Drowsiness
5. Anaemia
6. Miscarriage
7. Inability to participate in economic activities
8. Increased medical expenses

Prevention and control of Typhoid

1. Wash hands after visiting the toilet
2. Food and water must be protected from dust and flies
3. Wash hands before and after eating
4. Drink boiled water and eat properly cooked food; fruits should be washed thoroughly before being eaten.
5. Vaccination can also help to control the disease

Treatment: The disease can be treated by using antibiotics such as tetracycline,chloramphenicol, etc.

Effects

1. Can cause death
2. May cause ulcers and finally rupture of the intestine
3. Enlarged spleen

Prevention and control of T.B

1. Elimination of the conditions under which TB thrives e.g. overcrowding, poverty level living and inadequate nutrition.
2. Observing general personal hygiene, especially when coughing and sneezing.
3. Early BCG (Bacillus Calmette-Guérin) VaccineThe Vaccine may be used for either of two reasons:(i) Protecting newly-born babies or children at particular risk of infection.(ii) Immunization of young persons or at risk groups in the community.
4. Keeping children, in particular, away from risk situations.
5. The use of sterilized milk and pasteurized dairy products
6. Contact tracing so that risk to others may be minimized

Treatment: Antibiotics such as streptomycin can be used to cure the disease.

Effects of T.B

1. Causes a number of deaths.
2. Abscess full of pus may form near the lump in the spine.
3. Shortening and thickening of the chest in case of TB of the spine.

Human Immune Deficiency Virus (HIV) Acquired Immune Deficiency Syndrome (AIDs)

The Meaning of HIV/AIDs, STIs, and STDs

Explain the meaning of HIV/AIDs, STIs, and STDs

HIV stands for Human Immunodeficiency Virus, and AIDS for Acquired Immune Deficiency Syndrome. It is thought that AIDS originated from central Africa. The HIV Virus which causes the disease appears to have migrated Via Haiti to the USA. The term acquired means become infected and immune deficiency means lack of immunity

Sexually transmitted infections (STIs), also referred to as sexually transmitted diseases (STDs) and venereal diseases (VDs), are infections that are commonly spread by sex, especially vaginal intercourse, anal sex and oral sex. Most STIs initially do not cause symptoms.

There are more than 30 different sexually transmissible bacteria, viruses and parasites. The most common STIs they cause are gonorrhoea, chlamydia, syphilis, trichomoniasis, chancroid, genital herpes, genital warts, human immunodeficiency virus (HIV) infection and hepatitis B infection.

Sexually Transmitted Infections (STIs) and Sexually Transmitted Diseases(STDs)

Causes, Symptoms, Mode and Transmission and Effects of HIV/AIDs, STIs and STDs

Explain causes, symptoms, mode and transmission and effects of HIV/AIDs, STIs and STDs

Cause

Is caused by HIV (Human Immunodeficiency Virus).The Virus attack the body's immune system weakening it and making it more susceptible to infections and some cancers.

It is important to realize that, infection with the HIV virus does not necessarily result in AIDS. As with other diseases, some people remain symptomless and are said to be carriers.

Types of HIV Viruses

There are two major types of HIV Viruses, HIV 1 and HIV 2.HIV 1 is the most predominant virus and it is more easily transmitted while HIV 2 occurs in a small number of people in West Africa, Angola, Mozambique and some parts of India. It is less virulent.

Where in the body can you find HIV viruses? The virus in the body can be found in the following body fluids: blood, semen, vaginal fluid, tears, saliva and urine and breast milk. It is observed that semen, blood and vaginal fluids are more infectious.

Signs and symptoms of AIDS

A person infected with HIV may start to show signs of illness as from few weeks to many years. The infected individual may experience the following signs and symptoms:

1. Tremendous loss of weight
2. Persistent fever
3. Chest pain
4. Diarrhoea for no obvious cause
5. Coughing for more than one month
6. Shortness of breath getting worse over several weeks
7. Itchy skin rashes
8. Thrush in the mouth and throat
9. Loss of hair

Transmission

AIDS can be transmitted through any of the following ways:

1. Sexual intercourse with an infected person
2. Transmission from the mother to the baby during pregnancy, birth or breast feeding.
3. Sharing sharp objects with infected people e.g. sharing needles, razor blades, tooth brushes etc.

AIDS-related complex

The infected person may exhibit a variety of conditions. Common bacterial, fungal and viral infections attack the victim. These are known as opportunistic infections. They include diseases like pneumonia, T.B, meningitis, candidiasis, cancer e.g. Kaposi’s sarcoma, etc.

The Preventive and Control Measures of HIV/AIDs, STIs and STDs

Outline the preventive and control measures of HIV?AIDs, STIs and STDs

Prevention of HIV/AIDS

1. Use the ABC method to prevent the disease: A-Abstain from sex B- Be faithful to your only partner C- use Condom. This means that you are advised to abstain completely from sexual intercourse. If you can't then have one faithful partner and if this seems to be difficult then use condoms.
2. Avoid sharing sharp tools with the infected individuals
3. Blood transfusion should be done prior to HIV screening
4. Pregnant mothers should attend clinic so that they get treatment that will prevent HIV transmission from the mother to the baby.
5. Avoid all the risk behaviours, situations and practices that may enhance HIV transmission. The risk behaviours include drug abuse, prostitution, rape, anal sex, oral sex, alcoholism, unsafe sex, roaming in bars, guest house, etc.

Management of STIs and HIV/AIDs

Ways of Avoiding Risky Situations, Risky Behaviours and Practices

Explain ways of avoiding risky situations, risky behaviours and practices

Risky behaviours can be avoided by:

1. Practising safe sex
2. Applying non- penetrative sex e.g. kissing, hugging, etc.
3. Delaying technique e.g. I’m required at home just now lets meet tomorrow
4. Discouraging/negative words e.g. I’m HIV positive
5. Discouraging peer pressure
6. Engaging in sports and games which distract one’s mind from concentrating to sex.
7. Showing a sense of dislike to express the way you are by wearing T-shirts, caps with various messages e.g. ‘say no to sex’, ‘practice safe sex’, ‘Mimi nimepima wewe je?’, ‘AIDS kills’ etc

Necessary Skills for Avoiding Risky Behaviours, Practices and Situations

Demonstrate necessary skills for avoiding risky behaviours, practices and situations

So far there is no cure for HIV/AIDS, but treatment is available. However, the disease can be prevented by the following ways:

1. Avoid sexual intercourse. It is possible to live a healthy normal life without having sexual intercourse.
2. Use a condom correctly every time you have vaginal sex. It is often hard to be sure that your partner is truly faithful and unaffected.
3. Avoid multiple partners. Don’t have more that one sexual partner.
4. Avoid alcohol and drug abuse as they affect your decision making ability thus leading you to unsafe sex.
5. Avoid sharing needles and other skin piercing tools. Needles can be contaminated and HIV can survive in a syringe for a month or longer.
6. Avoid contracting other STIs because they increase the chances of HIV and AIDS infection. For those who have been infected, they must get proper treatment from a qualified medical practitioner.
7. Avoid risky behaviours such as going to night clubs, negative peer pressure and taking alcohol or drug abuse. These might put you in danger of being infected.
8. Prevent mother to child transmission by: (a) counselling and treating the mother; (b) using caesarean section as a mode of delivery; (c) use of alternative feeding (milk) instead of breastfeeding; and (d) not sharing breast milk.
9. Prevent transmission through organ and tissue transplants by screening both the donor and the patient.
10. Prevent minor injuries which might lead to infection. This can be achieved through:(a) use of gloves; (b) use of sterile instruments; (c) avoiding direct contact with contaminated body fluids;(d) proper handling of contaminated human waste; and (e) decontaminating soiled surfaces and lined.
11. Effective treatment of the infected through: (a) administering anti-retroviral therapy; and (b) prompt treatment of opportunistic infections.

Care and Support of people living with HIV/AIDS (PLWHA)

The Importance of Providing Care and Support to PLWHA in the Family Community and at School

Explain the importance of providing care and support to PLWHA in the family community and at school

Importance of care and support to people living with HIV/AIDS (PLWHA) include the following:

1. It enables them to prolong their lives in case they are administered with ARVs.
2. It reduces fear of death.
3. It enables them to perform their daily activities without fear.
4. It reduces depression and self dislike.

Necessary Care and Support Services Provided to PLWHA in the Family, Community and at School

Outline necessary care and support services provided to PLWHA in the family, community and at school

People who are infected with HIV need care and support form their friends, families and the community, especially when they are ill. Friends and family members sometimes worry that they might be infected when caring for a person with HIV.

HIV cannot be passed on by touching, hugging, coughing, or sharing eating utensils. It is possible for people who are infected with HIV to live long healthy lives. You can help those who are infected by:

• showing love, respect and support;
• knowing the facts about HIV/AIDS and talking openly about the disease;
• helping to reduce stress and stressful situations;
• helping to provide balanced and nutritious meals;
• seeking for support from family and friends as well as from other people who are HIV positive;
• encouraging them to live with hope;
• encouraging them to be active. Do not stop them from doing things they like;
• spend time with the sick person. For example help them to prepare their meals, clean their rooms, make their beds and take them to a walk if they can walk. Encourage family and friend to do this too;
• encouraging them to get treatment if they are sick. Most infections are easily treated and cured, even if a person is HIV positive.
• Cleaning their houses, utensils, clothes, etc.;
• trying to relieve any pain the person may be feeling, for example by administering pain killers; and
• treating them with respect and dignity making them as comfortable as possible.

Precautions to be taken when handling PLWHA and STIs

1. There may be situations where you need to clean up body fluids or blood from someone infected with HIV. Do not touch body fluids such as blood, stool and urine with your bare hands. It is important to use rubber or plastic gloves or other barriers such as plastic bags or thick cloth to prevent direct contact. Make sure that you have these easily available at all times.
2. Wash the gloves or plastic bags in hot water every time after you have used them. Keep clothes and bedding with blood, diarrhoea or body fluids away from other washings.
3. Wash the bedding and clothes with soap. Hang them where there is a plenty of sunshine and air circulation to dry well.
4. Do not share toothbrushes, razors, skin piecing instruments, or needles
5. Cover your wounds with a clean and sterile bandage. Buy disposable gloves so that once used they are discarded.
6. Dispose off properly the vomits or bandages used when dressing wounds.
7. Learn about the ways HIV can and cannot be transmitted. Talk to your friends and family. Contact your local clinic for more information

The Effects of Discrimination and Stigma to People Living with HIV/AIDS to the Individual, Family and Society

Explain the effects of discrimination and stigma to people living with HIV/AIDS to the individual, family and society

HIV-related stigma and discrimination exist worldwide, although they manifest themselves differently across countries, communities, religious groups and individuals. Possible consequences of HIV-related stigma could be:

• loss of income and livelihood
• loss of marriage and childbearing options
• poor care within the health sector
• withdrawal of caregiving in the home
• loss of hope and feelings of worthlessness
• loss of reputation