Sec 2 Science Notes

Secondary 2 Science Notes

Application of Forces and Transfer of Energy (Phy)

• Interactions occur through the transfer of energy & application of forces

  • Interactions lead to changes of stability in the system

1. How do forces in nature affect us?

• Certain examples of such phenomenons include:

1. Landslides (caused by forces exerted by rapidly moving floodwater)

2. Strong Wind

3. Earthquakes (caused by tectonic plates)

4. Volcanic eruption (caused by tectonic plates)

5. Tsunamis (tidal waves) /Floods (caused by volcanic eruptions and underwater earthquakes)

6. What are the types of forces?

• A force is either push or pull as a result of interaction between 2 objects.

• There are 2 forces:

1. Contact force

• Contact forces are exerted by an object/body on another object/body through physical contact

• Examples include:

1. Friction

• Is a contact force

• The force that opposes motion between 2 surfaces in contact. (definition)

• It occurs while walking, parachuting, writing and lighting a fire with matchsticks

• Kinetic friction - exist between 2 surfaces/objects that rub against each other

• Static friction - exist between 2 surfaces/objects that are not moving relative to each other

1. Elastic force

• A force acting on a stretched or compressed elastic object to return it to its original shape.

1. Non-contact force

• Non-contact forces act between two objects that are not touching each other.

• Examples include:

1. Gravitational force

• Is a force that attracts 2 objects towards each other

• When a planet exerts a gravitational force on an object and pulls it towards its centre.

• The amount of gravitational force acting between two objects is determined by the masses of both objects and the distance between the centres of the objects.

  • The greater the masses of both objects, the stronger the force

  • The shorter the distance between the centres of the 2 objects, the stronger the force.

1. Magnetic force

• Is exerted between a magnet and another magnetic material or between 2 magnets. (iron, nickel, cobalt and steel)

• A magnet has a North Pole and South Pole

• Like poles repel each other

• Unlike poles attract each other

1. Electrostatic force

• A force has to be exerted by one thing on something else/body

• The force exerted on A by B

• Representing forces:

• A force can be represented by an arrow

  • The length of the arrow = magnitude of the force

  • The direction of the arrow = direction of the force

• Mass vs Weight:

  • What is mass?

    • Ans: It is a fundamental property of matter, representing the amount of matter in a given object

  • What is weight?

    • Ans**:** Gravitational force acting on an object.

  • What is the SI unit of mass?

    • Ans: kg (small caps)

  • How to measure mass?

    • Ans: A balance scale, spring balance or electronic balances*

• Different planets exert different amounts of gravitational force on an object due to the difference in their masses and sizes.

• The amount of gravitational force exerted by a planet on 1 kg of mass is the gravitational field strength (GFS), denoted by grams (g), of the planet

  • Gravitational field strength of the Earth = 10N/kg

  • Gravitational field strength of the moon = 1.6N/kg

• As the shape of Earth is not a perfect sphere, distances from the centre of Earth to different places on its surface are not the same. Hence, the weight of the object differs but the mass is always constant.

  • GFS= between 9.76N/kg and 9.83N/kg

• FORMULA:

  • Weight (N) = mass (kg) x gravitational field strength (N/kg) =mg

  • The gravitational field strength is always the same unless stated*

1. What happens when two or more objects interact?

• Changes in the state of rest/motion of an object

• A force can:

1. Move a stationary object

2. Change the speed of an object

3. Change the direction of a moving object

• A force applied to an object to cause a turning effect about a fixed point

1. Stop a moving object

• The change in motion in an object can be caused by friction

• Friction can cause a moving object to slow down and eventually stop.

• Friction CANNOT accelerate an object.

• Changes in pressure on an object:

• Pressure: an effect of force acting on an object

• It is affected by the amount of forces exerted and the area of contact on which the force is exerted.

• Calculating pressure:

• Its defined as force per unit area

• SI unit of pressure = Newton per square metre (N/m2)/ Pascal (Pa)

• FORMULA:

• Pressure (Pa) = {Force\ (N)}{Area\ (m^2)} =(F/A)

• Examples of high pressure: a needle, a slim knife, stilleto heels

• Examples of low pressure: A thick bag strap, a tank

• An object experiences higher pressures as it goes deeper in a liquid.

• Atmospheric pressure:

• It is when the layer of air particles surrounding Earth pushes down on Earth’s surface due to gravitational force and exerts pressure (about 100,00 Pa) at sea level.

• When the distance from sea level increases, the amount of atmospheric pressure exerted decreases.

• Examples of atmospheric pressure:

1. Drinking straw

• Air is sucked out of the straw and creates a vacuum. The differences in the atmospheric pressure (little to no) and the vacuum within the straw forces the liquid to travel up the straw.

1. Suction cup

• When a suction cup is pressed against the wall, it forces the air particles between the suction cup and wall out, creating a vacuum. The differences in the atmospheric pressure and the vacuum between the surface of the suction cup and wall holds the suction cup to stick on the wall.

• Transfer of energy due to application of forces

• When a force is applied causes an object to move in the same direction as the force, it results in a transfer of energy

• When the energy is transferred, work is done through the application of forces.

• SI unit of energy and work done = joule (J)

• FORMULA

  • Work done (J) = Force (N) x Distance moved (m) = fd

• For work to be done, these criterias must all be fulfilled:

1. A force is applied on the object

2. The object moves

3. The object moves in the same direction as the force applied on it.

4. How is energy conserved?

• Different forms of energy exist around us (E.g: kinetic energy, potential energy, electrical energy, sound energy, light energy, thermal energy, etc.)

• The SI unit of energy = joule (J)

• The Law of Energy Conservation: energy cannot be created or destroyed, but can be converted from one form to another

  • The total energy of the car remains constant because energy is conserved.

  • Energy is transferred from one object to another, or converted from one form to another

  • The various forms of energy at each point will always add up to the total energy.

Transfer of Heat Energy and Its Effects (Phy)

• Expansion of solids, liquids and gases is caused by heat energy being absorbed

• Thermal expansion causes a change in volume, hence the density of the substance changes

• Contraction of solids, liquids and gases is caused by heat energy being given out

• Temperature

• Refers to how hot or cold something is

• SI Unit = Kelvin (K)

• Change in temperature causes matter to expand or contract, causing a change in its volume yet their mass remains the same

• Heat energy is transferred from a region of high temperature to a region of lower temperature

• Expansion and contraction

• Solids: Railway tracks and concrete slabs

• Expansion gaps between each railway track/ slab provides space for them to expand without any damage

• Liquids: thermometers

• A thermometer works due to the absorption of thermal energy from the surroundings and the liquid levels differ based on the temperature

• Effects of temperature change

• Metal pipes carry hot liquid/gas and expands/contracts depending on the temperature of the surrounding or substance

• Application of expansion and contraction

• Bimetallic strips

• Consists of 2 metals that expands at different rates (brass and iron are riveted together)

• The brass expands more than iron when heated. Hence, the heated strip bends with the brass on the outside of the curve.

• As the brass cotracts more than iron, the strip bends with the iron on the outside of the curve

• When the temperature changes, the different expansion rates of the coil makes it to either unwind or tighten.

  • Coil expands and unwind when temperature increases

  • Coil contracts and tightens when temperature decreases

  • The unwinding or contraction of the coil makes the pointer attached to it to move over a scale.

• The rivets:

• Used to join steel plates and girders (long metal beads)

• When it is red-hot, the rivet is put into position and is hammered into the head, allowing it to cool

• When it is cool, it contracts and pulls the steel plates together.

• Conduction, Convection and Radiation

• Conduction

• Definition: The transfer of thermal energy through a medium without any flow of the medium

• Particles at the heated end vibrate vigorously, colliding with neighbouring particles and transferring their energy

• Eventually, the particles at the cooler end also set into vigorous vibration

• Process of transfer of heat energy through a medium (especially solid) without its movement

• The transfer of thermal energy through the molecular vibration of particles.

• Conduction and convection can ONLY occur in mediums. When a vacuum is present/there is a lack of a medium, only radiation can occur

• Solid Conduction

  • E.g: Copper is the best for solid conduction as the transfer of thermal energy is the highest

  • Due to the presence of free electrons in metals like copper, thermal energy is transferred through the vibration and collision of particles

• Solids are better conductors of thermal energy than liquids and gases because its particles are more closely packed together

• Metals are good conductors of thermal energy while non-metals are insulators/ poor conductors of thermal energy

• Convection

• Process of transfer of heat energy in a fluid (liquid or gas) by circulation of fluids, due to a difference in density.

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  • When matter is heated, it expands and increases in volume. As the mass stays the same, the density decreases and the less dense substance floats/rises.

• When a fluid is heated, it expands, becomes less dense and rises. The denser fluid flows in to take its place.

• Convection is the transfer of heat energy by current movements in fluids due to density differences

  • When matter is cooled, it contracts and decreases in volume. As the mass stays the same, the density increases and the denser substance sinks

• A refrigerator: The refrigerator cools its contents by convection. The freezing unit cools the air at the top of the refrigerator as the cooled air is denser and therefore sinks. Warmer air form the bottom rises, replacing the cooled air. Thus, this sets up a convection currents that cools the interior of the refrigerator.

• Using a smouldering rope: As the air is heated by the flame of the candle, it rises and creates a vacuum. The differences in atmospheric pressure in the lamp shield and the surrounding air causes the air from the other lamp-shield to travel to the candle. Therefore, when the smouldering rope produces smoke, it has a higher density than the surrounding air sinks into the lamp-shield and travels towards the candle. It gains heat from the flame of the candle and its volume increases, hence decreasing its density, allowing it to rise.

• Sea Breeze (during the day): The solid land absorbs heat energy from the sun and warms up faster than the sea as solids are better thermal conductors than liquids. The atmospheric air above land is heated up and rises. The cooler, denser air above the sea moves in to replace the warm air above the land. Hence, causing sea breezes.

• Land Breeze (at night): The land loses heat energy faster than the sea and cools down faster. Air above the sea is now warmer and rises. Cooler, denser air above the land movies in to replace the warm air above the sea.

• Radiation

• Transfer of thermal energy does not require a medium

• Transfers through forms of waves (infra-red)

• Hotter the body, higher the rate of radiation

• Heat can radiate across vacuum

• Paint buildings in white or black?

  • Paint them white as it is a good reflector and poor absorber of thermal radiation. Hence, it is easier to keep the building cool.

• Double–glazing windows

  • Trapped air between the layers of glass helps to reduce thermal energy lost through conduction

  • Ventilation like air conditioners create convection currents within the building and decrease the surrounding temperature.

• Vacuum Flask

  • The cap: usually made of a poor thermal conductor (thermal insulator) like plastic

  • Plastic or Cork stopper: the mouth of the flask is stopped using a poor thermal conductor (thermal insulator) and prevents heat loss through convection into the surroundings

  • Vacuum: created between the glass walls by removing air. Conduction and convection cannot take place in a vacuum

1. Nature of surface

• Dull, black and rough surfaces = good radiators and absorbers, poor reflectors

• Shiny, silvery and smooth surfaces = poor radiators and absorbers, good reflectors

1. Total surface area of body

2. Surface temperature

• Global Warming

• Carbon dioxide traps thermal energy and keeps the earth warm. The increase of its amount in the atmosphere contributes to global warming

• It has both natural and man-made causes. For example:

1. Natural causes include volcanic eruptions and organisms

2. Man-made/human activity: burning of fossil fuels in power stations, factories and motor vehicles, which produce large quantities of carbon dioxide.

Chemical Change (Chem)

• Types of chemical change:

1. Respiration

2. Thermal decomposition

3. Combustion

4. Oxidation

5. When an acid reacts with a carbonate, salt, carbon dioxide and water are produced (NEUTRALISATION)

• E.g: hydrochloric acid + calcium carbonate (CaCO3) → carbon dioxide gas + calcium chloride (salt) + water

  • As the carbonate has a presence of carbon dioxide (CO2), it produces the carbon dioxide gas. To find out if the gas produced is actually carbon dioxide, we can bubble carbon dioxide (produced in a test for CO2) into a test tube of limewater through a delivery tube. Carbon dioxide gas is produced when white precipitate (solid) forms in the limewater.

• acids + alkali → salt (metal sulfate/chlorite/nitrate) + water

• acids + carbonate → salt (metal sulfate/chlorite/nitrate) + water + carbon dioxide

• acids + metals → salt (metal sulfate/chlorite/nitrate) + hydrogen

1. Acidity of a solution (The pH scale)

• The range of a pH scale is from 0 - 14

  • The smaller the value, the more acidic

  • Values of 0 - 6 are increasingly acidic (e.g: vinegar, tap water)

  • Values of 8 - 14 are increasingly alkali (e.g: carbonate, soap)

  • Value of 7 are neutral pH (e.g: pure water, eggs)

Universal indicators

• in the form of a solution or paper

• changes colours when added to different substances to correspond to a pH value between 0 to 14 on the pH scale.

• From 0 to 6, it turns from red to yellow. From 7 to 14, it turns green to blue to purple.

• Common indicators:

  • Phenolphthalein: colourless in acids, pink in alkalis (used to test alkalis only)

  • Methyl orange: red in acids, yellow in alkalis

  • Bromothymol blue: yellow in acids, green in neutrals and blue in alkalis

  • Red litmus paper (turns blue in presence of alkali, stays red in presence of acid/neutral)

  • Blue litmus paper (turns red in presence of acid, stays blue in presence of alkali/neutral)

  • Natural indicators ( red cabbage juice (pink in acid, green in alkali) and hydrangea flowers (blue in acidic soil, pink in alkaline soil) )

Questions:

1. What happens when sodium hydroxide is added into a solution of hydrochloric acid?

   • Salt and water are produced in the form of a colourless solution

2. What will happen when the mixture is heated strongly?

   • The water will evaporate and the salt is left as residue.

   • The solution boils to dryness and leaves behind a white residue. This is because NEUTRALISATION took place in the reaction when the sodium hydroxide was added to the hydrochloric acid in which salt, sodium chloride, is formed together with water.

3. Why do antacids relieve the discomfort caused by excess acid in the stomach.

   • Antacids contain alkaline compounds that can neutralise the excess acid in the stomach.

4. What happens when magnesium is added to hydrochloric acid?

   • Vigorous bubbling occurs and the magnesium dissolves into the colourless solution.

   • Magnesium reacts with the acid to produce hydrogen gas and a white solid, magnesium chloride (salt)

5. What happens when calcium carbonate is added to hydrochloric acid? - Effervescence (very vigorous bubbling)/ vigorous bubbling was observed.

6. What happens to the limewater?

   • It turns chalky/ cloudy due to the exposure to carbon dioxide.

Interaction with the Ecosystems (Bio)

Actions with negative impacts (limited earth resources and pollution):

1. food wastage

• Growing crops/livestock for food requires water, energy, minerals, and land in the soil and other limited resources on Earth.

  • Greenhouse gases are emitted during the production and transportation of food, and when food waste rots in landfills

• Food wastage wastes Earth’s limited resources and accelerates climate change

1. Increasing electrical consumption

• Using and maintaining technology (vehicles, smart devices, data clouds etc.) requires a lot of energy

  • Burning fuel is one way to generate electricity and emits carbon dioxide. However, there is only a limited amount of natural fuels on Earth (fossil fuels and natural gas)

• Increases the release of greenhouse gases (CO2), causes temperature to rise and ice caps to melt

  • Increase in sea levels can affect coastal areas

  • The ocean absorbs a high amount of carbon dioxide, causing an increase of ocean acidification

  • Presence of greenhouse gases also increases air pollution

1. Increasing water consumption

• Fresh water is a very limited resources (less than 1% on Earth)

  • The increase in water consumption will deplete fresh water more quickly

• Water scarcity may result in a shortage of food crops

  • The lack of access to clean water may cause sanitation issues, leading to diseases and death

  • Potential wars may break out over water as it is spread across geographic boundaries.

1. Creating excessive waste

• Waste needs to be properly disposed as improper waste pollutes the air, water and land

• Waste improperly disposed in the ocean can poison or kill marine organisms

  • Accelerated climate change as waste releases methane gas

  • Plastic pollution in oceans can affect aquatic life

Actions with positive impact (conserving the environment)

1. Reducing use of fossil fuels

• Reduces the use of fossil fuels to power cars and electrical appliances

• Reduce buying stuff that you do not need

  • Reuse items more than once

  • Disposing waste at the appropriate recycling locations

1. Reducing consumption

• Reduces the need to consume limited resources from the production and transportation of stuff, reducing the need for raw materials like wood which reduces deforestation

1. Introducing environmental friendly practices

• Reduces the emission of greenhouse gases and hence, affects climate change

• Contribute to the RecycleRight Campaign in CCHY

  • Donate old books and clothes

  • Compost food waste

1. Reforestation

• Protects the soil, which stores carbon.

  • Photosynthesis by plants take in carbon dioxide from the atmosphere, hence helping to store carbon.

• Plant own plants (vegetables, herbs, fruits, trees)

Physical factors of the environment:

1. Temperature

2. Humidity

3. Presence of minerals in soil

4. Availability of water

5. Acidity/Alkalinity of soil

6. Light intensity

• What makes up an ecosystem?

1. Individual (an organism adapted to the environment it lives in)

2. Population (organisms of the same kind lives in the same environment)

3. Community (different populations of plants and animals live and interact in an environment)

4. Ecosystem (interactions between a community and the physical environment)

• Types of interrelationships in an ecosystem

  • Predator-prey

    • predator hunt and kill their prey for food

    • Predators’ adaptation allow them to hunt successfully (sharp teeth, strong claws, fast speed etc.)

    • To avoid being caught, preys’ adaptation aids them to avoid being eaten (high speed, small size, effective camouflage, mimicking unpleasant objects etc.)

  • Mutualism

    • < 2 support or benefit one another

    • A type of close association formed between pairs of species where all species involved benefit.

  • Parasitism

    • Parasite causes harm to the host (another organism) without killing it

    • The parasite benefits by obtaining its food or nutrients from the body of a host (plant or anima) without killing it

• The maintenance of such interrelationships are important in keeping the balance in an ecosystem.

• The stability of an ecosystem can be disrupted by changes in the environmental conditions or the removal of any organisms

  • It may cause some organisms to decrease in number or even become extinct

  • By monitoring biodiversity of an ecosystem, it provides timely warning about potential threats to the stability of the ecosystem.

• To maintain the interrelationships of an ecosystem, it requires energy and nutrients

  • In an ecosystem, the transfer of energy occurs together with the flow of nutrients

  • Photosynthesis and respiration are some key processes involved in transferring energy and nutrients in the ecosystem. Others include feeding and decomposition.

    

→The primary consumers eat producers and are eaten secondary consumers and so on

→ The flow of energy is from one trophic level to another

→ Many food chains in an ecosystem can be represented in a food web

→ Energy flow from one level to another is decreasing

• A habitat is where an organism lives and have its own certain environment

• Different environments are distinguished by physical factors that can be measured using instruments (data loggers, pH meters and probes)

• A suitable combination of physical factors allows plants to grow and thus provide animals with food and shelter

• Only organisms that are suited to live in certain environments can survive long enough to reproduce as they have adapted to their environment/ have adaptive traits that enable them to grow well in their environments.

• Adaptive traits in an organism do not develop immediately within one generation in response to changes in the environment. They are developed over many generations.

Adaptations in organisms:

• Adaptive traits are:

1. Structural Adaptations

• Physical characteristics of an organism that help it survive in its habitat

  • colour and shape

1. Behavioural Adaptations

• Different behaviours of an organism that allows it to survive in its habitat

  • stillness (to disguise itself as an inanimate object to hide from predators and hunt)

Changes in environment:

• Physical factors of an environment and adaptive traits determine whether an organism can grow well in the habitat.

• When a physical factor changes, the survival of the organisms are affected and may die under the new conditions

• When new organisms are introduced into a habitat, the stability of the ecosystem is affected.

How does an environment influence the survival of organisms?

Our interactions with the world can lead to changes/influences the stability of a system. Thus we must make responsible choices.

Science and technology development influence the way we interact with the environment and vice versa.

Electrical Systems

• the rate of flow of charge = electric current (measured with an ammeter, SI unit = A, ampere)

• property of a component opposing the flow of electric current = resistance (measured with resistors, SI unit = Ω, ohm)

• The amount of electrical energy to drive a unit charge from one point to another = potential difference (measured with a voltmeter, SI unit = V, volt)

• To measure the flow of electric current, ammeters must be connected in series in the circuit, next to positive charge.

• To measure the potential difference in the circuit, voltmeters must be connected in parallel.

• resistors connected in parallel: total resistance will be smaller than smallest resistor

• Safety hazards:

1. damaged insulation → exposed wires →when someone touches it, will receive electric shock/electrocuted

2. overloading of plugs → drawing large currents through the sockets →overheating/excessive heat → electric fire

Digestive System (different organs working together to carry out a specific function)-

Nutrients:

• Carbohydrates

  • starch (complex and simple starch)

  • fiber

  • sugar

• Fats/Lipids

• Proteins

System/Organs (All parts of the human digestive system are needed for the digestion of food in the human body):

digestion can occur in both acidic environments (stomach) and slightly alkaline environments (small intestine)

• Mouth = Enzymes in the saliva break down food particles into smaller substances

• Gullet/Oesophagus = the smaller food matter is transported from the mouth and into the stomach (peristalsis)

• Liver= secretes bile and process/purify the blood containing newly absorbed nutrients that are coming from the small intestine.

• Galbladder= stores bile

• Pancreas= makes pancreatic juices called enzymes that break down sugars, fats, and starches

• Stomach = Enzymes in stomach acid further break down the smaller food particles into simpler substances

• Small Intestine (Duodenum, Jejunum, Ileum) = digestion has been completed (the site where most nutrients and water is absorbed)

• Large Intestine (Colon, Rectum, Anus) = undigested matter is transported here (the site where the remaining water is absorbed)

  • Colon: absorbs water and mineral salts from undigested food

  • Rectum: temporarily stores the remaining undigested food as faeces

  • Anus: faeces leaves the body and passes through the anus

substrate —————enzyme—————> product(s)

What are Enzymes?

• complex proteins that speed up the rate of chemical reactions

• are specific in their actions and act on only one type of substance

simple sugar vs complex sugar:

• simple sugars are made up of 1-2 sugar molecules

• complex sugars are made up of thousands of sugar molecules

Different Enzymes:

1. carbohydrase (substrate = carbohydrate)

• carbohydrate (starch)—— amylase ———> maltose

• maltose (starch)———- maltase —————> glucose

• carbohydrate (starch) ———— carbohydrase —————> simple sugars (general formula)

1. protease (substrate = protein)

   • protein —————— protease ——————> amino acids/smaller protein chains

2. lipase (substrate = lipid)

   • lipids ————— lipase ——————> fatty acids + glycerol

Importance of digestion:

• As the cell membranes of cells are partially permeable, larger molecules of food cannot pass through.

  • Therefore, digestion must take place to break down these large molecules (starch, protein and fats) into smaller soluble molecules. In this way, these smaller molecules can pass through the cell membrane and be absorbed into the blood.

Human Transportation System

• Cells need oxygen and nutrients to respire, grow and repair.

• There are many cells in a multicellular organism.

• Cells are far away from the source of these essential substances.

Diffusion is the net movement of molecules from a region of higher concentration to a region of lower concentration down a concentration gradient

Osmosis is the net movement

Surface area to volume ratio:

• for a cube with a 1cm length= 6:1

• for a cube with a 2cm length= 24: 8 = 3:1

• for a cube with a 3cm length= 54:27 = 2 : 1

E.g: Amoebas

• does not have a cell well (has a flexible and non-rigid shape)

• undergoes phagocytosis (extension of cytoplasm in order to engulf and absorb a foreign cell to eliminate/for food.)

Types of blood vessels:

1. Capillaries (the site of exchange of substances like waste materials, nutrients, oxygen)

   • rate of blood flow is low such that more substances can be diffused in and out of the capillaries at a faster rate

2. Arteries (carry oxygenated blood Away from the heart)

   • rate of blood flow is high

3. Veins (carry deoxygenated blood and waste materials towards the heart to the capillaries)

   • rate of blood flow is high

Blood composition:

1. Red blood cells - contains haemoglobin to transport oxygen to all parts of the body

   • circular and biconcave - increased exposed surface area to the oxygen such that more haemoglobin can absorb more oxygen, making the red blood cells more oxygen-rich

   • flexible and elastic membrane - easily absorbs oxygen (for cellular processes) and light energy (under light microscope)

   • no nucleus

   • smaller in size with a longer lifespan (3 months)

2. White blood cells - produces antibodies to help fight off infection, serving as a protective function

   • round

   • round nucleus

   • larger in size with shorter lifespan

3. Plasma - yellowish liquids that is the medium to transport hormones and antibodies

4. Platelets - plays a part in blood clotting

Plant Transportation System

1. Leaves (photosynthesis occurs here and produces sucrose/sugars)

2. Xylem (carries water and dissolved mineral salts from roots in an upwards direction to all parts of the plant)

3. Phloem (transport manufactured food; sucrose and amino acids from the green leaves in both upwards and downward direction to all parts of the plant)

4. Roots (absorbs water and mineral salts from the surrounding soil)