These are tools that make work easier by increasing the effort distance.
These are simple tools that make work easier by changing the direction of the force.
They are used to lift or raise load on higher surfaces.
A rope or string is put along the groove. The groove prevents the rope from slipping off.
The law of energy conservation statesthat, energy cannot be created or destroyed but can be changed to other forms of energy.
|Forms of energy||Sources|
|Potential energy (stored)||Possessed by objects at rest.
Found in fuels, dammed, water, elastic rubber.
|Kinetic energy (motion)||Possessed by moving objects.
Found in running water, wind, moving stone, moving car etc.
|Chemical energy||Found in chemicals, fuels, food, car battery, dry cells, candlewax and all fuels|
|Heat energy||Main source is sun.
Other sources include; friction, burning fuels, electricity and food.
|Light energy||Main source is sun.
Other sources include; stars, electricity, lamps et
|Magnet energy||Found in magnets, loadstones and electromagnet|
|Sound Energy||Produced when objects vibrates.
Sources include; pianos, guitas, drums etc
|Mechanical energy||Produced as a result of potential energy and kinetic energy.
Examples include; rotating turbines, hammer stricking a gong, between a bicycle and road
|Elastic potential||Found in streched rubber band or compressed spring.|
Energy conservation means protecting, preserving, restoring and managing energy resources.
Infants are children below 2years.
The best food for them is breast milk as it is wholesome ie it contains all the nutrients required by the body.
This is the gradual introduction of semi solids foods to an infant. It is done at the age of 4-6months. Breast feeding should continue upto 2 years. Introduce one food item at a time.
This is an illness of the stomach caused by eating foods containing harmful substances.
Environment describes all the things and conditions that make up our surroundings on earth.
The major natural components of environment consist of living things and non-living things i.e. Water, Soil, Air, Plants and Animals
Water is a very important component of the environment in that all living things depend on water. Water forms part of the environment for fish as fish get oxygen from the water and feed on water plants or some other fish found in the water. All other living things that live in water get oxygen from the water.
Other water sources found in the environment is a dependent for other living things on the land e.g. animals get water from rivers, lakes, rain and dams. People also use rain water for domestic purposes. They harvest the water using tanks and drums. They also
fetch water from rivers and wells.
Without water plants can not grow well. We already know that the conditions necessary for germination are: water, air and warmth. During photosynthesis, plants use water to make their own food.
Another important component of environment is soil which makes the homes of some small animals. Plants get nutrients from the soil so as they can grow well, get water from the soil through absorption and are finally held by the soil. Also soil is important to
animals in that they feed on plants that grow on the soil e.g. zebra, cows and goats. They are called herbivorous because they feed on green plants and vegetable materials that grow on the soil. Human beings cultivate the soil to produce food crops that they eat.
Many small animals live in the soil like ants, termites, moles, groundhogs and some bacteria which decompose dead plant and animal materials.
One of the major components of the environment is air which all living things cannot survive without. We already know that air is a composition of many gases; oxygen which makes 21% of the air is needed for respiration.
Note that living things breath in oxygen and those animals that live in water get their oxygen from the dissolved oxygen in the water. Carbon dioxide in air is 0.03% which is used by plants in making their own food in presence of sunlight, a process called
photosynthesis. These plants give out carbon dioxide. It is from the atmosphere where the plants and animals on the land get their oxygen and those in water get theirs in the water.
Animals take in oxygen through breathing and give out carbon dioxide. On the other hand plants take in carbon dioxide during photosynthesis and give out oxygen. Leguminous plants e.g. beans, ground nuts and peas use nitrogen which makes 78% part
of the air to make proteins.
Another major component of the environment is plants. Trees provide shelter for some animals such as monkeys and insects. Animals get their food from plants either directly or indirectly. Plants do also hold soil together thus preventing soil erosion.
Plants give out oxygen to the atmosphere during photosynthesis and animals take in oxygen during breathing. Dead plants decay and decompose releasing nutrients to the soil making it fertile.
Some animals help in pollination such as bees and butterflies. They help in cross pollination of flowers in plants. Animals also help in seed dispersal. Waste matters from animals add nutrients to the plants and this way soil becomes fertile. Small animals like
bacteria decompose materials in the environment to release nutrients to the environment. Animal breath out carbon dioxide into the atmosphere which in turn is used by plants to make food.
Soil pollution is the presence of substances that affect the quality of the soil also known as land pollution. It affects the usual use of soil and is dangerous to the health of human beings, other animals and plants. In other words, soil pollution means making soil impure. We say that when certain substances are present in the soil they pollute it. Substances that make soil or other components of the environment impure are called pollutants (contaminant). Some of examples of such pollutants are plastics, polythene papers, fertilizer, pesticides and herbicides.
NB: Pesticides kill pests while herbicides kill weeds.
If oil is spilled on the soil it pollutes it. The following are some causes of soil pollution:
When soil is polluted, its fertility is affected and this too affects the soil productivity leading to the living components of the environment i.e. plants and animals getting affected as well.
Most materials such as plastics and polythene papers do not decay. If such materials are not properly dumped, they may cause damage to leaves and stems of plants when deposited on the soil as they decay. Through this way, they interfere with growth of the plants as follows:
Soil being homes of many small animals, such as worms, ants and termites, they are negative affected when soil is affected (polluted). Some small animals like bacteria make soil to be rich by decomposing dead vegetable and animal materials. Thisis the way humus is added into the soil making it more productive. Other small animals like earthworms and millipedes dig in the soil and this allows air and water circulation in the soil. The improved soil aeration and drainage of the soil allows the roots of the plants to penetrate into the soil easily.
The presence of oil, chemicals in the soil such as herbicides and pesticides and other harmful pollutants make it difficult for the small animals to survive and when they die the soil losesits quality and lowers productivity.
NB: Small animals in the soil improve soil air aeration and drainage.
Animals and plants depend on soil. Plants grow on the soil while animals feed on the plants hence they need to conserve soil. To conserve soil means to protect it from losing its natural properties and productivity. There are various methods of conserving soil. This section briefly discusses these methods.
Table 3.1: Summary of the main methods used in soil conservation
|Soil conservation methods|
|Controlled use of agricutural chemicals||Planting trees|
|Ensruring proper disposal of waste||Afforestation|
|Avoid burning vegetable cover||Contour farming|
|planting ground cover||Proper stock ing or controlled grazing|
|Incinerator||this is burning the inorganic refuse at very high temperatures in a machine|
|Recycling||This is the most effective method. It involve collecting waste e.g. papers, plastics, broken glasses and food cans, treating them with chemicals and reusing them to make more of the same products|
|Depositing in pit latrines||Inorganic waste should be thrown into a pit latrine or buried deep in the soil. Also it can be burnt in an improvised incinerator as shown below.|
|Reusing||Reusing means using an item more then once or for a different function from the one it was meant for at the beginning. Many such as cooking fat and oils, honey and jam are packed in reusable jars and cans. These can be used at home to store other products e.g. salt, sugar or small foods. Honey jars can be used as drinking glasses.|
|On-site treatment||This is where waste is treated harmless at an industry at the point where it is produced. This in turn reduces the danger of polluting the environment during the transportation process to the point where it is appropriate to be disposed.|
|Reusing||Some industries use some products more than once or for different function from the initially meant for e.g. commercial industries, the solvent they use such as petrol to dry clean garments is not thrown away but filtered and reused.|
|Recycling||Companies that make bottles do not throw broken bottles away but recycle them to make new ones. There are other companies that buy waste paper and recycle them to make tissues e.g. toilet rolls, facial tissues and serviettes.|
|Waste Exchange Programme||One industry may produce waste that can or may be needed by another industry for its raw materials. This can be considered as useful waste. To explain this lets look at furniture manufacturer where the saw dust is produced and wood shaving as waste products. These can be used by a company that manufactures papers.|
|Treating hazardous waste||This is where the new methods are used to treat hazardous waste to make them non-hazardous. Harmful pollutants are destroyed so that they do not pose any danger to the environment.|
|This is the process where the raw materials that produce harmful wastes are replaced with other that produces less harmful waste.|
|Changing Manufacturing process||A process or stage which produces waste during the manufacturing process may be changed or eliminated so that the waste is no longer produced.|
|Incineration||This is the process of burning waste using machines such as incerators and furnaces.|
|Reducing its generation||This is the best method of reducing waste. It involves simply preventing waste generation.|
|Government regulations||In this, government has put in place laws to control the disposal of waste. Such control aims at preventing illegal dumping of harmful waste.|
Air is an important component of the environment. Pure air is a mixture of 21% oxygen, 78% nitrogen, 0.03% carbon dioxide and 0.97% rare gases, water vapour, and dust particles. Presence of harmful substances in the air is called air pollution. The substances are called pollutants. Pollutants endanger human health and also affect other living components in the environment i.e. plants and animals. Others which arte indirectly affected by air pollution are water and soil.
Polluted air is a threat to human, animals and plant life. Also it is dangerous to nonliving components of the environment e.g. water and soil. It corrodes materials such as corrugated iron sheets and marble.
Air pollution is controlled in several ways: These include;
Table 3.4: Air Pollution Control Measures
|Avoid smoking cigarettes||In an effort to control air pollution banning of cigarette smoking in public places e.g. hospitals, schools, and in public transport vehicles has been done. These areas have been declared smoking free zones and billboards displaying the ban in these areas have been erected.|
|NOT burning tyres and plastic materials||Polythene papers and tyres plus other plastics should be recycled or buried deep in the soil. They should not be burnt|
Hard water is water which contains dissolved salts ie magnesium and calcium. Mainly from sea,
oceans, boreholes, lakes and dams.
Soft water is water with no or little dissolved salt in it. Mainly rain water.
There are two types of water hardness, namely;
Temporary water hardness can be removed by boiling or distillation. Permanent water hardness can be removed by adding chemicals.
NB: The process of removing the dissolved minerals from hard water is called softening.
These are mammals that feed on plants eg cow, buffalo, antelopes, elephants etc
They are classified into two, namely;
|Horny pad||Hard, horny pad on the upper jaw.||Holding food tightly against incisor when cutting.|
|Diastema||Toothless gap between||For turning vegetable|
|Incisors and premolar||materials for proper chewing.|
|Incisors||They have incisors on the lowerjaw which are sharp, flat and chisel-shaped||Biting, holding, nibbling and cutting food.|
|Molars and premolars.||Present in both jaws.
Same size and shape.
Large, flat and ridged.
|For grinding, crushing and chewing food|
|Continous replacement of
molars and premolars
|Molars and premolars replace continous throughout their life.||To replace the worn out ones due to constant grinding of food materials.|
|Cow's tongue||Long and rough.||Long to reach out and grip grass.
Rough to avoid injury by hard vegetation.
|Horse and rabbit's
|Large, has certain bacteria.||Used for digesting tough plants materials called cellulose.|
|Camel's hump||Fats stored in hump.||Releases metabolic water when oxidised and
burned in the body.
These are mammals that feeds on flesh only. They include; lions, dogs, cats, leopard, etc
Adaptations of carnivores.
These are birds which feeds on grains or seeds.
They include; chicken, doves, Turkey, pigeons,Weaver bird and quelea birds. They have a strong, short, straight, thick, blunt and cone shaped beaks for picking grains.
Their claws are adapted to scratching.
They are know us birds of prey.
They include Hawks, eagles, kites and falcons
They have short, thick, sharp and hooked(curved) beaks for cutting and tearing flesh.
They have a sharp eyesight for spotting their prey from far.
They have strong,sharp and curved claws called talons for holding and tearing their prey.
They feed on nectars.
Examples include; sunbird and humming bird.
They have a long slender and slight curved beak for sucking nectarsfrom a flower.
These birds filters their foods from mud.
They include; ducks, sea gulls, swans, geese, pelican and flamingo.
They have a flat, broad, strong and serrated (v-shaped) beaksfor sieving or filtering their foods
Their feet are webbed.
Reasons for movement.
They have a powerful hind legs to enable them move forward. Some have a
short fore legs and strong hind eg kangaroo. Some also have tails for balancing.
They include; amphibians, grasshopper, locust and kangaroos.
Adaptations are mechanisms that enable a plant to survive in a habitat. Plants habitats include:-
Plants that are able to survive in dry area are called xerophytes.
Examples include: Cactus, acacia, euphorbia, baobab, sisal, marram grass, pricky pears, desert
shrubs, sun dune grass, jacaranda, thorn tree, cassava, casuarinas and candelabra.
They are called hydrophytes.
Most they grow in equatorial forests, swamps, marshes, lakes and rivers.
They include: water lily, butter cup, mangroves, bladderwort, water lettuce, duck weed, aquatic
ferns, rice plants and water hyacinth.
Plants which grow in normal soil and water conditions are called mesophytes.
They includes maize, beans, potatoes and bananas.
These are diseases which are passed from one person to another person through sexual contact.
They are also called sexual transmitted diseases (STDs)
|STI||Cause and transmission||signs and symptoms|
NB: Genital herpes and HIV/AIDS are other STIs caused by virus.
Fertilization is the fusion or union of the nuclei of the ovum and the sperm in the
There are two types of Fertilization that takes place in the female's body. Namely;
Process of Fertilization in human beings
During sexual intercourse/coitus/copulation, sperms are introduced in the vagina by the penis.
Sperms swim in the semen using their tails until they reach the oviduct where they meet a
Many sperms surrounds the ovum but only one penetrates the ovum, the nuclei of the sperm
and the ovum fuse to form a Zygote
After fertilization a woman becomes pregnant and this is called conception. NB: The sperms
which do not penetrate the ovum are killed.
The zygote then undergo cell division, travels down to uterus and attaches itself on the uterine walls, this is called implantation
After implantation, the zygote is called embryo
After implantation, the embryo develops a disc-shaped organ called placenta which joins the
embryo to the mother.
At 6weeks the embryo has formed most of the important body organs such as the
lips, nose, arms, ears, eyes, feet and toes.
At 8weeks(2months), the embryo is called foetus. The foetus is surrounded by the amnion which
contains a fluid called amniotic fluid.
NB: Gestation period takes nine months or 36 to 40weeks or 280days in human beings, this is
the period between conception and birth.
It is also called parturition.
When the foetus is fully developed, the head faces downwards and is positioned directly above the
Stages in the birth process.
This is the removal of waste productsfrom the body.
There are 3 main excretory organs, namely;
Waste products removed by these organs are;
Water, salt, urea and lactic acid forms sweat
Water, urea and salt forms urine.
|Excretory organs.||Excretory waste removed|
|Skin||Excess water, salt, urea, lactic acid.|
|Lungs||Excess water, carbon dioxide.|
|Kidneys||Excess water, urea, salt.|
Study the map of Bego Area below and use it to answer questions 1 to 7.
The diagram below shows a marine fishing method.
Use the map of Eastern Africa below to answer questions 30 to 33.
SECTION B: CHRISTIAN RELIGIOUS EDUCATION
During the Exodus the Israelites askedMoses to give them
SECTION II: ISLAMIC RELIGIOUS EDUCATION