Study Notes on Science Content Topics
Living World
Living and Non-Living Things
Characteristics of living organisms: Growth, reproduction, metabolism, response to stimuli, adaptation, cellular organization, homeostasis, excretion
Plants
Types based on structure:
Herbs: Small plants with soft, green stems (e.g., mint, coriander)
Shrubs: Woody plants with multiple stems (e.g., rose, jasmine)
Trees: Tall woody plants with single stem/trunk (e.g., mango, neem)
Types based on habitat:
Terrestrial: Grow on land (e.g., oak, maple)
Aquatic: Grow in water (e.g., lotus, water lily, hydrilla)
Desert: Adapted to arid conditions (e.g., cactus, aloe vera)
Plant parts and functions:
Roots: Anchor the plant, absorb water and minerals
Stem: Supports the plant, transports water and nutrients
Leaves: Site of photosynthesis
Flowers: Reproductive organs
Fruits: Contain seeds for reproduction
Seeds: Embryonic plant with stored food
Animals
Classification based on reproduction:
Oviparous: Animals that lay eggs (e.g., birds, reptiles, most fish)
Viviparous: Animals that give birth to young ones (e.g., humans, cats, dogs)
Classification based on food habits:
Herbivores: Eat only plants (e.g., cow, rabbit, elephant)
Carnivores: Eat only animals (e.g., lion, tiger, wolf)
Omnivores: Eat both plants and animals (e.g., humans, bears, crows)
Bird beaks: Adapted to their feeding habits
Hooked (eagles): Tearing flesh
Pointed (woodpeckers): Drilling holes
Conical (sparrows): Cracking seeds
Flat (ducks): Filtering water
Animal sounds: Different animals make distinct sounds (e.g., dogs bark, cats meow, lions roar)
Movements in animals: Walking, running, flying, swimming, crawling, slithering
Habitats and adaptation: Animals develop specific features to survive in their environment
Aquatic: Streamlined body, fins, gills (fish)
Desert: Water conservation, nocturnal habits (camel)
Polar: Thick fur, layer of fat (polar bear)
Human Beings
Body parts: Head, neck, trunk, arms, legs
Healthy body habits:
Regular exercise
Balanced diet
Proper hygiene
Adequate sleep
Regular health check-ups
Sense organs and their care:
Eyes: Vision (avoid reading in dim light, take breaks from screens)
Ears: Hearing (avoid loud noises, keep ears clean)
Nose: Smell (avoid inhaling harmful substances)
Tongue: Taste (maintain oral hygiene)
Skin: Touch (keep clean, protect from sun)
Skeletal system:
Bones: Provide structure and protection
Joints: Allow movement
Cartilage: Cushions joints
Muscles: Enable movement through contraction and relaxation
Safety measures:
Home safety: Fire safety, electrical safety
School safety: Playground rules, lab safety
Road safety: Traffic rules, crossing roads safely
Water safety: Swimming with supervision, life jackets
First aid: Basic techniques for minor injuries
Food
Need for food: Energy, growth, repair, protection from diseases
Sources of food:
Plants: Grains, fruits, vegetables
Animals: Milk, meat, eggs
Types of food:
Carbohydrates: Energy-giving foods (rice, wheat, potatoes)
Proteins: Body-building foods (pulses, meat, eggs)
Fats: Energy reserve foods (oils, butter, ghee)
Vitamins & Minerals: Protective foods (fruits, vegetables)
Balanced diet: Contains all nutrients in appropriate amounts
Food preservation methods:
Drying/dehydration
Refrigeration
Freezing
Canning
Salting
Pickling
Agricultural practices:
Traditional farming
Organic farming
Modern agriculture (mechanization)
Tools: Plough, tractor, harvester
Cell - The Basic Unit of Life
Definition: Smallest structural and functional unit of living organisms
Types of cells:
Prokaryotic cells: No defined nucleus (bacteria)
Eukaryotic cells: Have a defined nucleus (plants, animals)
Cell structure:
Cell membrane: Controls movement of substances
Cytoplasm: Jelly-like substance where organelles are suspended
Nucleus: Control center containing DNA
Mitochondria: Powerhouse of the cell; produces energy
Chloroplasts: Found in plant cells; site of photosynthesis
Endoplasmic reticulum: Transport system within cell
Golgi apparatus: Packaging and secretion
Lysosomes: Contain digestive enzymes
Vacuoles: Storage (larger in plant cells)
Microorganisms
Types:
Bacteria: Single-celled prokaryotes
Viruses: Non-cellular entities that require host cells
Fungi: Includes yeast, mold, mushrooms
Protozoa: Single-celled eukaryotes
Algae: Photosynthetic microorganisms
Useful microorganisms:
Food production: Yogurt, cheese, bread
Medicine: Antibiotics
Agriculture: Nitrogen fixation
Waste decomposition
Biogas production
Harmful microorganisms:
Disease-causing (pathogens)
Food spoilage
Crop damage
Life Processes
Nutrition
Types of nutrition in plants:
Autotrophic: Make their own food through photosynthesis
Parasitic: Derive nutrients from host plants (e.g., Cuscuta)
Saprophytic: Obtain nutrients from dead/decaying matter (e.g., fungi)
Insectivorous: Trap and digest insects (e.g., Venus flytrap, pitcher plant)
Human digestion:
Mouth: Mechanical breakdown, starch digestion begins
Esophagus: Transports food to stomach
Stomach: Protein digestion begins, kills bacteria
Small intestine: Main site of digestion and absorption
Large intestine: Water absorption, waste formation
Liver & pancreas: Produce digestive enzymes and bile
Digestion in grass-eating animals:
Four-chambered stomach (ruminants)
Cecum and appendix in herbivores help digest cellulose
Bacterial fermentation breaks down cellulose
Respiration
Types:
Aerobic: Requires oxygen
Anaerobic: Without oxygen (fermentation)
Respiration in animals:
Lungs in mammals, birds, reptiles
Gills in fish
Tracheal system in insects
Skin in amphibians (partial)
Respiration in plants:
Through stomata in leaves
Through lenticels in stems
Through root surface
Circulation
Human circulatory system:
Heart: Four-chambered pump
Blood vessels: Arteries, veins, capillaries
Blood: Plasma, red blood cells, white blood cells, platelets
Transport in plants:
Xylem: Transports water and minerals upward
Phloem: Transports food throughout plant
Excretion
In humans:
Kidneys: Filter blood, form urine
Skin: Sweat glands remove waste
Lungs: Remove carbon dioxide
In plants:
Falling leaves
Excretion through stomata
Storage of waste in vacuoles
Reproduction
In plants:
Sexual: Through flowers, fruits, seeds
Asexual: Vegetative propagation (buds, runners, tubers)
Seed dispersal methods:
Wind (dandelion)
Water (coconut)
Animals (burrs)
Explosion (touch-me-not)
In animals:
Sexual reproduction
Asexual reproduction (budding, fragmentation)
Human reproduction:
Adolescence and puberty: Physical and hormonal changes
Sex determination: XX (female), XY (male)
Reproductive health: Hygiene, disease prevention
Natural Phenomena
Objects and Materials
Properties of materials:
Physical: Hardness, malleability, conductivity
Chemical: Reactivity, acidity/alkalinity
Metals and non-metals:
Metals: Good conductors, malleable, ductile, lustrous
Non-metals: Poor conductors, brittle, non-lustrous
Reactivity series: K > Na > Ca > Mg > Al > Zn > Fe > Pb > Cu > Hg > Ag > Au
Separation methods:
Filtration
Evaporation
Distillation
Chromatography
Magnetic separation
Acids, bases, and salts:
Acids: Sour taste, turn blue litmus red
Bases: Bitter taste, turn red litmus blue
Salts: Formed by neutralization of acids and bases
Physical vs chemical changes:
Physical: No new substance formed (e.g., melting, freezing)
Chemical: New substance formed (e.g., rusting, burning)
Light
Properties:
Travels in straight lines
Can reflect, refract, disperse
Can form shadows
Transparent, translucent, opaque objects:
Transparent: Light passes through completely (glass)
Translucent: Some light passes through (frosted glass)
Opaque: No light passes through (wood)
Reflection:
Regular: Smooth surfaces (mirrors)
Diffused: Rough surfaces
Mirrors:
Plane mirrors: Same size image
Concave mirrors: Can magnify or diminish
Convex mirrors: Always diminished image
Human eye:
Parts: Cornea, iris, pupil, lens, retina
Common defects: Myopia, hypermetropia, astigmatism
Braille system: Reading method for visually impaired
Electricity
Electric circuit components:
Battery/cell: Source of electricity
Conductors: Allow electricity to flow
Insulators: Block electricity
Switch: Controls flow
Load: Uses electricity (bulb, motor)
Effects of electric current:
Heating effect: Used in heaters, irons
Magnetic effect: Used in motors, bells
Chemical effect: Used in electroplating
Safety devices:
Fuse: Melts when current exceeds safe limit
MCB: Modern version of fuse, can be reset
Magnetism
Properties of magnets:
Attract magnetic materials
Have two poles (North and South)
Like poles repel, unlike poles attract
Always point North-South when freely suspended
Types of magnets:
Natural (lodestone)
Artificial (bar, horseshoe, ring)
Temporary
Permanent
Magnetic compass: Uses Earth's magnetic field for direction
Heat
Temperature: Measure of hotness or coldness
Units: Celsius, Fahrenheit, Kelvin
Heat transfer:
Conduction: Through solids
Convection: Through fluids (liquids and gases)
Radiation: Through space/vacuum
Force, Friction, and Pressure
Force: Push or pull that can change an object's motion
Contact forces: Applied through direct contact
Non-contact forces: Act at a distance (gravity, magnetism)
Friction: Resistance to motion between surfaces
Factors affecting friction: Surface roughness, normal force
Ways to reduce friction: Lubricants, ball bearings, streamlining
Ways to increase friction: Rough surfaces, treads
Pressure: Force per unit area
Fluid pressure: Increases with depth
Atmospheric pressure: Decreases with altitude
Sound
Production: Vibration of objects
Propagation: Travels as waves through medium (solid, liquid, gas)
Properties:
Pitch: Depends on frequency (high/low)
Loudness: Depends on amplitude
Quality/timbre: Depends on waveform
Human ear: Outer ear, middle ear, inner ear
Types of waves:
Longitudinal: Particles vibrate parallel to wave direction
Transverse: Particles vibrate perpendicular to wave direction
Sound pollution: Harmful effects and prevention
Our Universe
Moon: Earth's natural satellite
Phases: New moon, full moon, quarter moons
Surface: Craters, maria (seas)
Eclipses:
Solar eclipse: Moon between Sun and Earth
Lunar eclipse: Earth between Sun and Moon
Stars and constellations:
Constellations: Group of stars forming patterns
Pole star: Nearly stationary star indicating North
Solar system:
Sun: Center of solar system
Planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
Other members: Asteroids, comets, dwarf planets
Artificial satellites: Man-made objects orbiting Earth
Transportation and Communication
Transportation
Modes of transport:
Land: Roads, railways
Water: Rivers, oceans
Air: Airplanes, helicopters
Transportation in different regions:
Hilly areas: Ropeways, special vehicles
Deserts: Camels, special vehicles
Snowy areas: Sleds, snowmobiles
Water bodies: Boats, ships
Transport of goods: Import and export
Communication
Types:
Verbal: Speech, writing
Non-verbal: Gestures, expressions
Mass communication: Media reaching large audiences
Means of communication:
Traditional: Letters, postcards
Modern: Telephones, mobile phones, internet, email, social media
Impact: Brings the world closer; global connectivity
Our Environment
Climate and Weather
Climate change: Long-term changes in temperature and weather patterns
Causes: Greenhouse gases, deforestation
Effects: Global warming, rising sea levels, extreme weather
Disaster management: Preparation and response to natural disasters
Air
Components: Nitrogen (78%), Oxygen (21%), Carbon dioxide (0.04%), other gases
Properties:
Has mass
Occupies space
Can be compressed
Exerts pressure
Air pollution:
Causes: Vehicle emissions, industrial emissions, burning waste
Effects: Respiratory problems, acid rain, global warming
Prevention: Reduced emissions, alternative energy, afforestation
Water
Forms: Solid (ice), liquid (water), gas (water vapor)
Water cycle: Evaporation, condensation, precipitation, collection
Water resources:
Surface water: Rivers, lakes, ponds
Groundwater: Wells, springs
Water pollution:
Causes: Industrial waste, sewage, agricultural runoff
Effects: Waterborne diseases, harm to aquatic life
Treatment: Filtration, chlorination, sewage treatment
Biodiversity
Forests: Natural ecosystems with trees and undergrowth
Benefits: Oxygen production, habitat, soil conservation, water cycle
Flora and fauna: Plants and animals in an ecosystem
Conservation:
Protected areas: National parks, wildlife sanctuaries
Endangered species: Threatened with extinction
Endemic species: Found only in certain regions
Environmental issues:
Deforestation and its effects
Chipko movement: Forest conservation movement in India
Plastic pollution
Green house effect
Acid rain
These notes cover the key concepts in the science curriculum for Class III to VIII with a difficulty level up to Class X. They are structured to provide a clear overview of each topic with important subtopics and essential details.
100 Multiple Choice Questions on Science Content
Living World
Which of the following is NOT a characteristic of living organisms? A) Growth B) Reproduction C) Magnetism D) Response to stimuli
Answer: C) Magnetism
Plants with multiple woody stems from the base are classified as: A) Herbs B) Shrubs C) Trees D) Climbers
Answer: B) Shrubs
Which type of plants has adapted to survive in water-scarce conditions? A) Aquatic plants B) Terrestrial plants C) Desert plants D) Parasitic plants
Answer: C) Desert plants
Which plant part is primarily responsible for photosynthesis? A) Roots B) Stem C) Leaves D) Flowers
Answer: C) Leaves
Animals that lay eggs are called: A) Viviparous B) Oviparous C) Herbivores D) Carnivores
Answer: B) Oviparous
Which of the following animals is an omnivore? A) Cow B) Lion C) Crow D) Deer
Answer: C) Crow
The hooked beak of an eagle is specialized for: A) Cracking seeds B) Filtering water C) Tearing flesh D) Drilling holes
Answer: C) Tearing flesh
Which of the following is NOT a sense organ? A) Eyes B) Ears C) Heart D) Nose
Answer: C) Heart
Which of the following provides structure and protection to the human body? A) Muscles B) Bones C) Skin D) Fat
Answer: B) Bones
Which of the following foods is rich in carbohydrates? A) Fish B) Rice C) Eggs D) Milk
Answer: B) Rice
Cell and Microorganisms
The smallest structural and functional unit of an organism is: A) Tissue B) Cell C) Organ D) Molecule
Answer: B) Cell
Which of the following is unique to plant cells but absent in animal cells? A) Cell membrane B) Nucleus C) Chloroplast D) Mitochondria
Answer: C) Chloroplast
The control center of the cell that contains DNA is the: A) Mitochondria B) Nucleus C) Lysosome D) Vacuole
Answer: B) Nucleus
Which of the following is NOT a type of microorganism? A) Bacteria B) Virus C) Fungi D) Platelets
Answer: D) Platelets
Which microorganisms are responsible for converting milk into yogurt? A) Viruses B) Bacteria C) Algae D) Protozoa
Answer: B) Bacteria
Life Processes
Plants that make their own food through photosynthesis are called: A) Heterotrophs B) Autotrophs C) Parasites D) Saprophytes
Answer: B) Autotrophs
Venus flytrap is an example of a plant with which type of nutrition? A) Autotrophic B) Parasitic C) Saprophytic D) Insectivorous
Answer: D) Insectivorous
Which organ is the main site of digestion and absorption in humans? A) Stomach B) Small intestine C) Large intestine D) Liver
Answer: B) Small intestine
Which of the following animals has a four-chambered stomach? A) Human B) Fish C) Cow D) Snake
Answer: C) Cow
Respiration that requires oxygen is called: A) Anaerobic respiration B) Aerobic respiration C) Photosynthesis D) Fermentation
Answer: B) Aerobic respiration
Through which structures do plants primarily carry out respiration? A) Roots B) Flowers C) Stomata D) Fruits
Answer: C) Stomata
Which blood vessels carry blood away from the heart? A) Veins B) Arteries C) Capillaries D) Venules
Answer: B) Arteries
In plants, water and minerals are transported through: A) Phloem B) Xylem C) Epidermis D) Stomata
Answer: B) Xylem
The main excretory organ in humans is: A) Liver B) Heart C) Kidney D) Lungs
Answer: C) Kidney
The dispersal of seeds by explosion is found in: A) Coconut B) Dandelion C) Touch-me-not D) Burrs
Answer: C) Touch-me-not
Natural Phenomena
Which of the following is NOT a property of metals? A) Good conductors of heat B) Malleable C) Poor conductors of electricity D) Lustrous
Answer: C) Poor conductors of electricity
In the reactivity series of metals, which of the following is most reactive? A) Silver B) Gold C) Potassium D) Iron
Answer: C) Potassium
Which separation method would be most suitable for separating iron filings from sand? A) Filtration B) Evaporation C) Magnetic separation D) Distillation
Answer: C) Magnetic separation
Acids turn blue litmus paper to: A) Green B) Black C) Red D) Yellow
Answer: C) Red
Which of the following is an example of a chemical change? A) Melting of ice B) Rusting of iron C) Dissolving sugar in water D) Cutting paper
Answer: B) Rusting of iron
Objects that do not allow light to pass through are called: A) Transparent B) Translucent C) Opaque D) Reflective
Answer: C) Opaque
What type of mirror is used in vehicle side-view mirrors? A) Plane mirror B) Concave mirror C) Convex mirror D) Bifocal mirror
Answer: C) Convex mirror
Which part of the human eye is responsible for controlling the amount of light entering? A) Cornea B) Retina C) Iris D) Lens
Answer: C) Iris
Which of the following is NOT a component of an electric circuit? A) Battery B) Switch C) Thermometer D) Conductor
Answer: C) Thermometer
The heating effect of electric current is used in: A) Electric motor B) Electric bell C) Electric iron D) Electric compass
Answer: C) Electric iron
Unlike poles of a magnet: A) Repel each other B) Attract each other C) Have no effect on each other D) Create electromagnetic fields
Answer: B) Attract each other
Heat transfer through empty space occurs by: A) Conduction B) Convection C) Radiation D) Condensation
Answer: C) Radiation
Which of the following is a contact force? A) Magnetic force B) Gravitational force C) Frictional force D) Electrostatic force
Answer: C) Frictional force
Fluid pressure increases with: A) Decrease in depth B) Increase in depth C) Decrease in density D) Decrease in area
Answer: B) Increase in depth
Sound waves are classified as: A) Transverse waves in all media B) Longitudinal waves in all media C) Longitudinal waves in solids only D) Transverse waves in liquids only
Answer: B) Longitudinal waves in all media
Universe and Environment
Which phase of the moon occurs when the entire illuminated side is visible from Earth? A) New moon B) Full moon C) First quarter D) Last quarter
Answer: B) Full moon
A solar eclipse occurs when: A) Earth comes between the Sun and Moon B) Moon comes between the Sun and Earth C) Sun comes between Earth and Moon D) Earth, Sun, and Moon form a right angle
Answer: B) Moon comes between the Sun and Earth
Which of the following is NOT a planet in our solar system? A) Mercury B) Pluto C) Neptune D) Mars
Answer: B) Pluto
The component present in the highest percentage in air is: A) Oxygen B) Nitrogen C) Carbon dioxide D) Water vapor
Answer: B) Nitrogen
Which of the following is a greenhouse gas? A) Oxygen B) Nitrogen C) Carbon dioxide D) Hydrogen
Answer: C) Carbon dioxide
The process of water changing from liquid to gas is called: A) Condensation B) Evaporation C) Precipitation D) Collection
Answer: B) Evaporation
Which of the following is NOT a cause of water pollution? A) Industrial waste B) Sewage C) Afforestation D) Agricultural runoff
Answer: C) Afforestation
The 'Chipko movement' is associated with: A) Water conservation B) Forest conservation C) Air pollution prevention D) Wildlife protection
Answer: B) Forest conservation
Transportation and Communication
Which mode of transport would be most suitable in hilly areas? A) Regular buses B) Ropeways C) Submarines D) Hovercraft
Answer: B) Ropeways
Which of the following is NOT a modern means of communication? A) Email B) Mobile phone C) Pigeon carrier D) Social media
Answer: C) Pigeon carrier
Additional Questions
The process by which plants make their food is: A) Respiration B) Photosynthesis C) Transpiration D) Digestion
Answer: B) Photosynthesis
Which of the following is the powerhouse of the cell? A) Nucleus B) Mitochondria C) Chloroplast D) Lysosome
Answer: B) Mitochondria
A balanced diet should contain: A) Only proteins B) Only carbohydrates C) All essential nutrients in proper proportions D) Maximum amount of fats
Answer: C) All essential nutrients in proper proportions
The specialized tissue that conducts impulses in the human body is: A) Muscle tissue B) Connective tissue C) Epithelial tissue D) Nervous tissue
Answer: D) Nervous tissue
Which of the following animals would have the strongest bones? A) Fish B) Birds C) Reptiles D) Mammals
Answer: D) Mammals
Deficiency of vitamin D causes: A) Night blindness B) Rickets C) Scurvy D) Beriberi
Answer: B) Rickets
The process of breaking down food into simpler substances is called: A) Assimilation B) Digestion C) Absorption D) Excretion
Answer: B) Digestion
In which state of matter are particles arranged in a fixed pattern? A) Solid B) Liquid C) Gas D) Plasma
Answer: A) Solid
Which of the following objects would float in water? A) A piece of iron B) A stone C) A wooden block D) A coin
Answer: C) A wooden block
The instrument used to measure atmospheric pressure is: A) Thermometer B) Barometer C) Hygrometer D) Anemometer
Answer: B) Barometer
Which sense organ helps in maintaining balance of the body? A) Eyes B) Nose C) Ears D) Tongue
Answer: C) Ears
The part of the plant that conducts food from leaves to other parts is: A) Xylem B) Phloem C) Epidermis D) Cortex
Answer: B) Phloem
Which of the following is an example of a biodegradable material? A) Plastic bag B) Aluminum can C) Fruit peel D) Nylon cloth
Answer: C) Fruit peel
The burning of fossil fuels contributes to: A) Ozone layer formation B) Air pollution C) Water purification D) Soil fertility
Answer: B) Air pollution
Which of the following diseases is caused by a virus? A) Typhoid B) Tuberculosis C) Influenza D) Cholera
Answer: C) Influenza
The speed of sound is highest in: A) Air B) Water C) Vacuum D) Solids
Answer: D) Solids
Which of the following is a physical change? A) Burning of paper B) Rusting of iron C) Melting of wax D) Digestion of food
Answer: C) Melting of wax
The device used to break an electric circuit in case of overload is: A) Switch B) Fuse C) Battery D) Conductor
Answer: B) Fuse
The acid present in lemon is: A) Acetic acid B) Citric acid C) Tartaric acid D) Lactic acid
Answer: B) Citric acid
Which of the following is NOT a natural resource? A) Air B) Water C) Plastic D) Soil
Answer: C) Plastic
The main function of white blood cells is: A) Transport of oxygen B) Clotting of blood C) Fighting against infections D) Regulation of body temperature
Answer: C) Fighting against infections
Which of the following animals has scales on its body? A) Frog B) Fish C) Pigeon D) Rabbit
Answer: B) Fish
The science that deals with the study of heredity is: A) Physiology B) Genetics C) Ecology D) Anatomy
Answer: B) Genetics
A device that converts electrical energy into mechanical energy is: A) Generator B) Battery C) Electric motor D) Solar cell
Answer: C) Electric motor
Which organ helps in removing nitrogenous wastes from the blood? A) Lungs B) Heart C) Liver D) Kidneys
Answer: D) Kidneys
The process by which water vapor changes into liquid water is called: A) Evaporation B) Condensation C) Sublimation D) Precipitation
Answer: B) Condensation
Which of the following is an example of a fossil fuel? A) Solar energy B) Wind energy C) Coal D) Hydroelectricity
Answer: C) Coal
The outer protective layer of the earth is called: A) Atmosphere B) Hydrosphere C) Lithosphere D) Biosphere
Answer: A) Atmosphere
Which of the following helps in blood clotting? A) Red blood cells B) White blood cells C) Platelets D) Plasma
Answer: C) Platelets
The phenomenon of light splitting into its component colors is called: A) Reflection B) Refraction C) Dispersion D) Diffraction
Answer: C) Dispersion
Which animal has a body divided into head, thorax, and abdomen? A) Fish B) Frog C) Snake D) Insect
Answer: D) Insect
The first step in the scientific method is: A) Experimentation B) Observation C) Analysis D) Conclusion
Answer: B) Observation
Plants absorb water from soil through: A) Leaves B) Stem C) Root hairs D) Flowers
Answer: C) Root hairs
Which of the following is NOT a renewable source of energy? A) Solar energy B) Wind energy C) Coal D) Tidal energy
Answer: C) Coal
The stage of complete development of a butterfly from an egg is called: A) Metamorphosis B) Fertilization C) Pollination D) Germination
Answer: A) Metamorphosis
The unit of measuring electric current is: A) Volt B) Watt C) Ampere D) Ohm
Answer: C) Ampere
Which gas is essential for combustion? A) Nitrogen B) Carbon dioxide C) Oxygen D) Hydrogen
Answer: C) Oxygen
The chemical formula for water is: A) H₂O B) CO₂ C) O₂ D) N₂
Answer: A) H₂O
Which of the following is a cold-blooded animal? A) Dog B) Cat C) Snake D) Human
Answer: C) Snake
The sense that helps us maintain balance and posture is: A) Vision B) Hearing C) Taste D) Equilibrium
Answer: D) Equilibrium
The process by which plants lose water in the form of vapor is: A) Photosynthesis B) Respiration C) Transpiration D) Condensation
Answer: C) Transpiration
Which of the following diseases is caused by lack of iron in the diet? A) Rickets B) Scurvy C) Anemia D) Goiter
Answer: C) Anemia
What causes day and night? A) Revolution of Earth around the Sun B) Rotation of Earth on its axis C) Rotation of the Sun D) Revolution of the Moon around Earth
Answer: B) Rotation of Earth on its axis
Which layer of the atmosphere contains the ozone layer? A) Troposphere B) Stratosphere C) Mesosphere D) Thermosphere
Answer: B) Stratosphere
The SI unit of force is: A) Kilogram B) Newton C) Joule D) Pascal
Answer: B) Newton
Which of the following is the largest organ of the human body? A) Heart B) Liver C) Skin D) Brain
Answer: C) Skin
Which of the following is NOT a function of the skeletal system? A) Support B) Protection C) Movement D) Digestion
Answer: D) Digestion
The process by which solid changes directly into gas without changing into liquid is called: A) Evaporation B) Condensation C) Sublimation D) Freezing
Answer: C) Sublimation
Which of the following is an example of a decomposer in an ecosystem? A) Tree B) Deer C) Fungi D) Wolf
Answer: C) Fungi
The average normal body temperature of a human being is: A) 37°C B) 32°C C) 42°C D) 25°C
Answer: A) 37°C