Introduction to Science

What is Science?

• Science involves the systematic study of phenomena that can be examined, tested, and verified.
• Basic Science introduces students to fields like Biology, Chemistry, Physics, and Agriculture.

How Science is Studied

• Science relies on:
  • Observation
  • Sorting
  • Experimentation
  • Recording results
  • Drawing conclusions
• Observation involves studying something carefully, using senses such as touch, hearing, and smell.
• Sorting groups items based on physical characteristics (color, size, texture) and behavioral characteristics (reactions to light, touch, chemicals).
• Experiments are conducted by scientists to test hypotheses, with the scientific investigation being called an experiment.
• Recording experiment results involves accurately documenting all observations for analysis and conclusion.
• Analysis of experiment results can prove a hypothesis right or wrong, and a repeatedly proven hypothesis becomes a theory.

Branches of Science

• Science is divided based on study focus or practical applications of discoveries:
  • Life Science deals with living things, including genetics, botany, and zoology, all studied under Biology.
  • Physical Science investigates matter and energy, including Physics, Chemistry, and Astronomy.
  • Earth Sciences examines the structure and composition of the planet, with divisions like Geology and Geography.
  • Social Sciences explores human society, including Political Science, Law, and Economics.
  • Mathematical Science researches relationships that can be measured or quantified.
  • Technology applies scientific knowledge to practical uses, like engineering machinery, materials, and industrial processes.

Applications/Usefulness of Science

• Science has many applications, including:
  • Medicine involving production of preventive and curative drugs.
  • Engineering that improves efficiency and saves resources.
  • Construction of infrastructure like houses, bridges, and skyscrapers.
  • Agriculture
  • Electricity generation
  • Communication

Family Health: Sanitation and Hygiene

• Sanitation promotes health through environmental cleanliness and proper waste disposal.
• Personal hygiene wards off diseases through practices like bathing, hand washing, teeth brushing, and wearing clean clothes.

Consequences of Poor Sanitation

• Poor sanitation results in:
  • Diseases like diarrhea and cholera from unclean water.
  • Potential death from diseases that are preventable.
  • Unpleasant environment with offensive odors and breeding grounds for pests.

Types of Sanitation

• Basic sanitation manages human waste at the household level, including toilet access.
• On-site sanitation involves waste collection and treatment at the site of deposit.
• Food sanitation maintains hygiene in food safety.
• Housing sanitation protects the home environment.
• Environmental sanitation manages solid and wastewater, industrial waste, noise pollution, and refuse disposal
• Ecological sanitation recycles nutrients from human and animal waste.

Waste and Types

• Wastes includes unwanted materials discarded by people, industries, and companies.
• Types of waste include:
  • Refuse which is dry or solid waste like paper, nylon, plastics, broken bottles, metal scraps, and bones.
  • Sewage which is liquid waste like urine, human feces, and wastewater from kitchens and bathrooms.

Refuse Disposal Methods

• Kitchen refuse should be collected in a lidded dustbin.
• Refuse can be burned in incinerators.
• Refuse can be composted.
• Refuse can be buried.
• Refuse can be used to fill swamps and lowlands.

Sewage Disposal Methods

• Pit latrines are deep pits in the ground used for sewage disposal where there isn't a regular water supply.
• Bucket latrines involve depositing feces and urine in buckets, which are then taken away; this method is outdated.
• Water closets (W.C.) or flush toilets are modern sewage disposal methods used where piped water is available.

Sanitation Tools

• Common sanitation tools:
  • Rake
  • Shovel
  • Spade
  • Cutlass
  • Brooms

Cleaning Tools and Agents

• Cleaning tools and agents maintain cleanliness and include items like:
  • Mop
  • Sponge
  • Detergents
  • Soap
  • Tissue paper
  • Dusters
  • Brooms
  • Brush
  • Scouring powder

Environmental Materials

• Environmental materials are grouped into:
  • Biodegradable materials such as vegetable waste and food processing waste that decay and can be broken down by microorganisms into simpler compounds; they can improve soil fertility when decomposed.
  • Non-biodegradable materials that cannot be decomposed and are major contributors to environmental hazards; recycling is needed.

Nutrition

• Nutrition studies nutrients in food and how the body uses food for growth and development.
• A balanced diet is key to staying healthy.
• Nutrients are chemical components that nourish the body, including proteins, carbohydrates, fats, minerals, vitamins, and water.
• Food provides energy for daily activities and supports growth, strength, and overall health.

Terms in Nutrition

• A meal is the amount of food consumed at one time.
• A diet is the type of food and drink consumed.
• Fat-soluble vitamins are those capable of dissolving in fats (A, D, E, K).
• Water-soluble vitamins are those that are soluble in water (B complex and C).

Classes of Food, Sources, and Functions

Fat-Soluble Vitamins

Water-Soluble Vitamins

Essential Minerals

Balanced Diet

• A balanced diet contains all six classes of food in correct proportions.
• An example is boiled rice, vegetable stew with meat, and orange juice.
• Importance of balanced diet:
  • To provide energy.
  • To maintain growth and repair.
  • To sustain healthy living.

Food Test: Starch

• A test for starch uses iodine solution.
• A blue-black color confirms its presence.
• Apparatus: Beaker, test tube, Bunsen burner, iodine solution, starch powder, various foods.
• Method: Boil starch powder with water, dilute the gel.
• Add iodine solution, and observe for blue-black color.

Drug Abuse

• Drugs are biochemical substances with positive/negative effects.
• They can be introduced via swallowing or injection.
• Drug use involves intended use with a doctor's prescription.
• Drug abuse involves misuse without prescription which includes substances like tobacco, coffee, alcohol, marijuana, Indian hemp, cocaine, and heroin, which have adverse effects.

Sources of Drugs

• Herbs, including roots, bark, leaves, and flowers of plants with healing properties.
• Micro-organisms, such as the fungus Penicillium used for penicillin production.

Medical Uses and Classification of Drugs

• Analgesics relieve pain, like aspirin and paracetamol.
• Antibiotics fight bacteria, like penicillin and streptomycin.
• Anaesthetics prevent sensation of pain.
• Anthelmintic drugs expel worms, which includes Ketrax and Combantrin.

How Drug is Abused

• Taking expired drugs.
• Overdosing
• Using drugs by unqualified people
• Using drugs inappropriately

Effects of Drug Abuse

• Health implications:
  • Death and madness.
  • Altered organ functions.
• Social effects:
  • Crimes and disobedience.
  • Addicts turning into touts, miscreants, and armed robbers.

Environmental Pollution

• Environmental pollution is waste discharge into water, land, or air.
• It renders the environment unsafe for living organisms.
• Pollutants are substances that pollute the environment.
• Types include:
  • Air pollution
  • Water pollution
  • Soil/land pollution

Types and Sources of Air Pollution

• Air pollution involves the release of toxic substances into the atmosphere, mainly in urban and industrial areas.
• Types of air pollutants:
  • Solid (dust, lead, pollen, carbon).
  • Liquid (liquid waste from factories).
  • Gaseous (carbon oxide, Sulphur oxide, nitrogen oxide)
• Sources: Incomplete combustion and refrigerators.

Effects of Air Pollution

• Choking, respiratory infections, and eye irritation.
• Acid rain from sulfur dioxide reacting with water vapor.
• Reduced photosynthesis

Water Pollution

• Water pollution occurs when pollutants contaminate water.
• Water pollutants and impacts:
  • Dirt: Clogs gills, reduces sunlight.
  • Bacteria: Carries diseases, increases carbon dioxide.
  • Fertilizers: Promotes algae growth.
  • Oil spills: Reduces oxygen.

Control of Water Pollution

• Encourage plant cover and discourage deforestation
• Septic tanks must not overflow and animals should not be allowed to roam to prevent their feces from entering the water
• Trained farmers in fertilizer application
• Site oil rigs away from residential areas and restrict Fuel Tankers movements

Sources of Water Pollution

• Domestic Wastes
• Agricultural Wastes
• Industrial Wastes
• Oil spillage
• Heated Water