Science-Interactive.co.Uk_Water Transport in Plants

7/24/2019 Science-Interactive.co.Uk_Water Transport in Plants

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Science Interactive LTD

Science Interactive LTD. PO BOX 50764 LONDON NW6 9AT email: [email protected] web: www:science-interactive.co.uk

Science Interactive LTD Copyright 2005

Science base multimedia CD-ROM for PC is a collection of 38 units or tools totalling over 1150

PowerPoint slides. Each unit covers a wide range of different delivery and learning styles, offering an

exciting way to involve your pupils during lessons or revision sessions. All styles of teaching and

learning are supported through use of high quality images, graphics, challenging exercises andquestions. Units can be used in the classroom via an interactive whiteboard, data projector or used

during individual study via a PC or school network.

Unit 19: The Transitional Metals

Unit 18: Metals and their Properties

Unit 17: The Alkali Metals

Unit 16: The Periodic Table and its Elements

Unit 15: Genetic Engineering

Unit 14: Evolution and Human Impact

Unit 13: Inheritance and Selection

Unit 12: Mitosis and Meiosis

Unit 11: Flow of Energy and Elements through the Environment

Unit 10: Water Transport in Plants

Unit 9: Photosynthesis in Green Plants

Unit 8: Drugs and Bad Body Maintenance

Unit 7: Hormones and the Endocrine System

Unit 6: Human Homeostasis

Unit 5: Nervous System and the Senses

Unit 4: The Respiratory System

Unit 3: Healthy Body and Immunity

Unit 2: The Circulatory System

Unit 1: The Digestive System

Unit 38: Cells, Tissue, Organs and Organs systems

Unit 37: Natural Forces

Unit 36: Sound and Hearing

Unit 35: The Alkaline Earth Metals

Unit 34: The Earth and Plate Tectonics

Unit 33: Earth and Space

Unit 32: Newton's Forces and the Effects of Forces

Unit 31: Radioactivity

Unit 30: Light and the Electromagnetic Spectrum

Unit 29: Electricity

Unit 28: Generating Electricity and its Domestic Use

Unit 27: Energy

Unit 26: Rates of Reaction

Unit 25: The Noble Gases, their Properties and Uses

Unit 24: The Halogens, their Uses and Compounds

Unit 23: Ionic and Covalent Compounds

Unit 22: Elements, Molecules and Compounds

Unit 21: Rock Cycle

Unit 20: Crude Oil and its Products


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Unit 10

Water Transport in Plants


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Unit 10: Water Transport in PlantsUnit 10: Water Transport in Plants Science Interactive LTD Copyright 2005

Understand: Keywords:

1. That plants, like other organisms require atransport system providing water forphotosynthesis.

2. The role of the root hair cell in absorbing waterand minerals from the soil.

3. That water passes from the soil to the root haircell by osmosis.

4. That the flow of water through the plant iscalled transpiration.

5. The factors that affect the rate of watermovement or transpiration in a plant.

6. The role of active transport in acquiring solubleessential minerals.

7. The role of fertilisers in improving crop yields.

8. The role of hydroponics in crop production.

9. That controlling greenhouse conditions liketemperature and light levels affects crop yields.

10. Some of the benefits and drawbacks ofintensive farming.

Water, Transport, Osmosis, Transpiration,

Root hair cell, Xylem, Phloem, Active

transport, Minerals, Nitrates, Phosphates,

Potassium, Stoma, Guard cells, Light,

Humidity, Temperature, Fertilisers, Manure,

Crops, Yield, Organic, Farming, Hydroponics,Greenhouse & Production.

web: www.science-interactive.co.uk email: [email protected] Interactive LTD PO BOX 50764 LONDON NW6 9AT

Click mouse to begin



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Plants as producersPlants as producersPlants are called producers because they produce all the Worlds biomass via a process called

photosynthesis. Plants use energy from the s_____ to combine carbon dioxide and w________

to form g__________ and oxygen. This reaction produces millions of tonnes of living matter,that nourishes all other living organisms in the animal kingdom. The oxygen that plants release

into the atmosphere is used in cellular r_____________ by all living organisms. How can we

determine the biomass of a plant ?

Plants as producers: Word bank: sun water glucose respiration

Plant yield: (kg per hectare)

14000

10000

6000

2000


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Photosynthesis and its equationPhotosynthesis and its equation oneone

6 molecules of CO2 6 molecules of H2O 1 molecule of glucose 6 molecules of O2

From the equation for photosynthesis we can determine the raw materials required during

photosynthesis. Sugar production in green leaves will only occur if w_______ and carbon

dioxide are supplied to the chloroplasts inside leaf palisade cells.

6CO2 + 6H20 C6H12O6 + 6O2

Carbon dioxide water light and chlorophyll Glucose Oxygen

Raw materials and photosynthetic products: Word bank: light

Glucose is produced

during photosynthesis

and transported by thephloem to all parts of

the plant.

Glucose

Oxygen is taken out

through the leaf during

daylight hours andreleased into the

atmosphere.

Water is taken from

the soil by the root hair

cells, through thexylem and into the leaf

space.

Carbon dioxide is

taken in during day

light hours through theleaf stomata cells from

the atmosphere.

Notes

Diagram

OxygenWaterCarbon dioxide



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Products

Substrates

C6H12O6 6O2

6H2O 6CO2

Activation energyNet energy taken

in during reaction

Progress of reaction

Potent

ialenergy

O2

H2O CO2

C6H12O6

In this reaction H2O

and CO2 substrates

are combined in the

plant leaf cells using

light energy to

produce glucose(C6H12O6) and O2.

KeyEnergy changes during photosynthesis

Reactions that take in energy from their surroundings in the form of heat or light are

called endothermic reactions. Although these types of reactions are not as common as

exothermic reactions, there are several examples. An important example of anendothermic reaction isphotosynthesis, whereby light e_________ is used to combine

water and carbon dioxide to form glucose and oxygen.

Photosynthesis reaction:

Photosynthesis and its equationPhotosynthesis and its equation twotwo

Word bank: energy



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py g

Overview of transporting waterOverview of transporting waterSeveral specialised c______ and tissues are involved in the transport of water and soluble

minerals like potassium and nitrates from the s______ to the leaf palisade cells. From the

root hair cells to the xylem, found in the stem and leaf, water moves through the plant in acontinuous transpiration stream. During photosynthesis, six molecules of this water are

combined with six molecules of c_________ d___________ to form one molecule of

glucose and six molecules of oxygen. Energy from s__________ drives this reaction.How

is water absorbed by the root hair cells form the soil ?

Cells and tissues transporting water: Word bank: cells soil carbon dioxide sunlight

Xylem tubes from the

leaf veins spreading out

to supply the palisadecells and tissue with

water during photo-

synthesis.

Leaf

Stomata cells on the

underside of the leaf

allow water vapour andoxygen out of the leaf

during the daylight

hours.

The water moves up the

stem through the xylem

vessels by capillaryaction. They are long

tubes reaching from the

roots to the leaf tissue.

Millions of root hair

cells with a huge surface

area line the surface ofplant roots. They take in

water from the soil into

the plant xylem.

Notes

Diagram

Root hair cell Stem Stomata



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Water into the rootWater into the rootThe root system, as well as anchoring the plant, takes water and m__________ salts from the

soil. The roots are covered by root h_____ cells. These highly specialised cells have a thin

membrane and large surface area. Water passes from the soil to the hair cells and then throughroot cells and finally to the xylem tissue by a process called osmosis.

Passage of water through the root:

Root hair cell

Xylem vesselWater

Soil

Cell A Cell B Cell C

Root cortex cellsRoot hair cell

Xylem vesselWater

Soil

Cell A Cell B Cell C

Root cortex cells

There is a higher concentration of water in the soil compared to the root hair cell. By osmosis, water

passes from the soil to the hair cell. Now there is a higher water concentration of water in the root

hair cellcompared to cell A. Water moves from the root hair cellto cell A. This also happens from

cell A to cell B. This continues across the whole root, where water eventually reaches the xylem.

Notes

Diagram

The pathway of water across the root into the xylem

Word bank: mineral hair


E l i i i


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Explaining osmosisExplaining osmosis

Outside cell Inside cell Outside cell Inside cell

Dissolved

salts

Water

Semi

permeablemembrane

Water movement by osmosis

equals out the amount of water

on both sides of the membrane.Large molecules are unable to

cross the membrane.

After(Complete)

Outside the cell membrane

there is a high concentration of

water compared to the inside.Water then begins to move

inwards by osmosis.

Water molecules are able

to move from one cell to

the next by a processcalled osmosis. This is

shown by the redarrows.

Notes

Diagram

Plant cells Before

Osmosis is the passage or movement of water from an area of high concentration to an area of

low concentration through a living semi permeable membrane. The water is in fact diffusing

from a weak solution into a stronger solution of a solute like sugar or salt. Tiny holes in theplant membrane allow water m___________ to pass through, whereas some solute molecules

are too large to pass through the membrane. This process also occurs in human cells and

requires no energy at all, unlike active transport.

Explaining osmosis: Word bank: molecules

ff fEff t f i l t d i l llScience Interactive LTD Copyright 2005


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Effects of osmosis on plant and animal cellsEffects of osmosis on plant and animal cellsPlant and animal cells both lose water, when placed in hypertonic solutions and gain water

when placed in hypotonic solutions, however the effects on animal and plant cells are

different. Animal cells have no cell w____ and vacuole, so they shrivel when losingw______ to a concentrated hypertonic solution and burst and die in a hypotonic solution.

Plant cells have a cell wall and vacuole, which both help to control the effects of gaining

or losing water inside the cell. What tough molecule is found in the plant cell wall ?

Water movement in plant and animal cells:

Plant cells are much more robust to the

movement of water. This is because of the

strong cell wall and the vacuole. The vacuole

shrinks or expands, helping to control the

plant cell shape. The cell wall adds strength

to the cell.

Animals cells are very sensitive to water

movement across their membranes. In

hypertonic solutions, water moves out of the

cell, causing the cell to shrivel. In hypotonic

solutions water moves into the cell, causing

the membrane to rip open.

Notes

Diagram

Animal cells Plant cells

Word bank: wall water


W t i th h th lW t i th h th l


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Water moving through the xylemWater moving through the xylemOnce water has entered the xylem from the soil, through the root hair cell and other root cells

by a process called osmosis, water moves through the xylem by capillary action. This requires

no e________ and relies on cohesion or the stickiness that exists between water molecules.Xylem vessels can be up to 100 metres in length in some plants, especially trees.

Water transpiration: Word bank: energy

Water

Soil

Evaporation

Cohesion

Osmosis

Root hair cell

Xylem

Leaf

Water vapour

Stoma

Air spaces

Vessel

Palisade cells

Waxy cuticle

Epidermis

The water is pulled up the xylem in the stem from the root system. Water is then used by

the palisade cells during photosynthesis. Water also evaporates from the leaf. As wateris lost from the leaf, it causes a continuous flow from the roots through the xylem to the

leaf. This is called transpiration or the transpiration stream.

Notes

Key Diagram showing movement of water through a plant


St tSt t oneone


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StomataStomata oneone

These specialised cells are found on the underside of the leaf and allow gases to diffuse in and

out.

1: Carbon dioxide diffuses in for photosynthesis.

2: Oxygen produced during photosynthesis diffuses out.

3: Water vapour diffuses out.

Stomata in detail:

Stomata cells open mainly during the day to allow the

passage of gases and water vapour. They can respond

to drier conditions by closing to reduce water loss.

Stomata are opened and closed by the guard cells

changing shape. These guard cells containchloroplasts providing the energy for opening and

closing.

Stomata

During photosynthesis plants need a constant

supply of water from the soil. The water exuded

from the surface of this green leaf is actually from

water vapour released from the leaf stomata. Only

on the underside of green leaves, will you findhundreds of stomata cells, although you need a

powerful light microscope to see them.

Notes

Diagram

Transpiration through plants Stomata up close

St tSt t twotwoScience Interactive LTD Copyright 2005


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0 2 4 6 8 10 12 14

Bod

ytemp

Microbe

normal37oC

time days12am 8 am 12pm 8pm 12am

Ox

ygen

CO2

Use

G

lucose

Night Dawn Daylight

time hrs

Dusk Night

0 2 4 6 8 10 12 14

Bod

ytemp

Microbe

normal37oC

time days12am 8 am 12pm 8pm 12am

Ox

ygen

CO2

Use

G

lucose

Night Dawn Daylight

time hrs

Dusk Night

Closed Open Closed

During the night, no photosynthesis takes place, just plant respiration. At duskand dawn when

the light intensity is low, the rate of respiration and photosynthesis are roughly the same.

During the d____, when there is greatest light energy, there is a net production of glucose andoxygen. The stomata cells, found on the underside of the leaf o_____ during daylight hours

when photosynthesis occurs and partially close during the night. Stomata are opened and closed

by the guard cells changing shape. These guard cells contain chloroplasts, which provide the

energy for stomata opening and closing

Effect of light intensity on stomata opening and closing:

StomataStomata twotwo

Word bank: day open

Notes

Diagram


Factors affecting transpirationFactors affecting transpiration


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Factors affecting transpirationFactors affecting transpirationTranspiration, the flow of water through a plant is affected by several factors. More

transpiration takes place during the day whilst photosynthesis occurs. During the night the

stomata cells are c________. In very dry conditions where the soil is dry, the stomataclose to reduce water loss, thereby preventing the plant from wilting. Losing too much

water through transpiration will reduce plant cell turgidity, allowing the plants to become

flaccid. If the plants are allowed to lose too much water, they can die.

Factors affecting transpiration rates: Word bank: closed

An increase in air

humidity will reduce the

rate of transpiration.

Humid air already

contains a very high

percentage of water.

Humidity

Air movement over the

plant leaves increases

the rate of evaporation

therefore increasing the

rate of transpiration of

water through plants.

Increases in temperature

increase the rate of water

evaporation from the

leaves surface as well

the rate of photosynthesis

in green plants.

Increasers in light

intensity increases the

rate of photosynthesis

and the need for water.

Stomata open during

day light hours.

Notes

Diagram

Light Temperature Air movement


M i th t f t i tiM i th t f t i ti


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Measuring the rate of transpirationMeasuring the rate of transpiration

Rateoftranspiration

Rateoftranspiration

Rateoftranspiration

Ra

teoftranspiration

0 4 8 1210 14 18 22

wind speed (km/h)temperature (oC) Humidity (%)25 50 75 100

Light intensity (lux)100 500 1000 1500

Graph

Humidity

Data logger potometer

Air movementTemperatureLightConditions

Potometer

Simple plant potometer

The rate of transpiration can be measured by using a potometer. A potometer measures the

rate of w______ uptake by a plant using a plant cutting with a stem and several. Potometers

can also be linked to a computer to give you second by second reading on water loss.

Measuring transpiration in plants: Word bank: water


Crop growth and developmentCrop growth and development


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Crop growth and developmentCrop growth and development

Growing from seed to mature plant requires the right amount of light, soil nutrients, warmth, water and

carbon dioxide. Farmers carefully control all these conditions to maximise their profits.

Notes

Diagram

Crop growth and development in corn from seed to mature plant

Good crop growth and development in wheat, rice, soya and corn are important so that we can

avoid hunger and starvation. Many billions of people depend on just four or five c______ for

their primary f______ source. Farmers have developed their knowledge of crop growth, so thatthey know good soil from poor, the right amount of temperature and light and other factors that

affect yield like using the right pesticides and herbicides. Name four other crops that are

commercially important for the human food chain ?

Factors affecting crop yields: Word bank: crop food

Plant nutrientsPlant nutrientsScience Interactive LTD Copyright 2005


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Plant nutrientsPlant nutrientsAll plants require several n__________ obtained from the soil for healthy growth. These

soluble nutrients like potassium and nitrates are taken up by the root by active transport. Unlike

water uptake, this requires energy. Soil, with a low concentration of these nutrients is usuallytreated by adding f____________ early on in the growth season.Essential nutrients include:

Potassium (K)Nitrogen in NO3- (N)Phosphates (P)

Effect of mineral deficiencies on plant growth:

Lack of Potassium:Poor growth rates,

yellow leaves with dead

spots.

Lack of Nitrogen:Stunted growth, low

protein content and

yellow older leaves.

Lack of Phosphates:Poor growth rates, poor

root growth and purple

younger leaves.

Normal healthy growth:Corn is an important

source of carbohydrates

in the human diet.

Notes

Nitrogen (N)

Diagram

Normal growth Phosphates (P) Potassium (K)

Word bank: nutrients fertiliser


Crop yieldCrop yield oneone


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Crop yieldCrop yield oneone

Good crop yields are important for everyone to avoid hunger and starvation. Farmers add

fertilisers at the beginning of every growing s________ to replace lost minerals from the soil.

These minerals are lost because of the intensive way farmers use land in Europe and the USA.Improving crop yields with fertilisers, p___________ and other factors cost farmers money.

Farmers have to work out how best to improve crop yield, whilst still making a profit when they

sell their products. Describe the differences for how organic and non-organic farmers improve

their crop yields ?

Factors affecting crop yields: Word bank: seasons pesticides

Plants need sufficient

water for healthy growth

and development. Low

rain fall can lead to poor

crop yields or even total

failure.

Water

Intensive crop farming

reduces the quality of the

soil, stripping all the

plant minerals. Farmers

add fertilisers at the start

of every growing season.

Increases in temperature

and light increases crop

yield. Most crops are

grown in the summer

when temperatures and

light levels are high.

Notes

Diagram

Crop yield in corn Temperature & light Fertiliser


Crop yieldCrop yield twotwo temperature & lighttemperature & light


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Crop yieldCrop yield p & gp g

Increases in temperature and light increases crop yield. Most crops are grown in the summer

when temperature and l______ levels are high. In fact in Northern Europe, no crops are grown

during the winter, because average temperatures dip below 6o

C. This is the point wherephotosynthesis stops happening. Very high temperatures (40oC) will rapidly dehydrate the crop,

if there is insufficient w______ in the soil. This will reduce overall yield in crops like corn,

wheat and rice. Other than water, what is the other substrate essential for photosynthesis in

green plants ?

Temperature affecting crop yields:

35oC30oC20oC15oCCrop yield in tomatoes

Word bank: light water


Crop yieldCrop yield threethree waterwater


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Crop yieldCrop yieldPlants need sufficient water for healthy growth and development. Low rain fall can lead to poor

crop yields or even total failure. Water irrigation is essential to grow crops in the drier areas of

Europe, where summer rainfall is low. In very dry areas like Northern Africa and the MiddleEast, crops are only grown near to rivers. Adjacent to the great river Nile in Egypt is where

90% of all crops are grown. In England, we rely on summer r________ rather than irrigation

systems. Explain why salt water cannot be used to support crop growth ?

Water affecting crop yields: Word bank: rainfall

Correct rainfallMedium rainfallLow rainfallVery Low rainfallCrop yield in tomatoes


Crop yieldCrop yield fourfour fertiliserfertiliser


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Crop yieldCrop yieldIntensive crop farming reduces the quality of the s_____, stripping all the essential plant

minerals. Farmers add fertilisers or manure at the start of every growing season. In areas with

very little or no mineral rich top soil, crop yield are very low. Some soils are so poor that theydo not support crop growth at all. Soil is also lost every year due to rain and wind e________.

Farmers have to be very careful to preserve their soil for the next years crop. Reducing soil

erosion, by mixing crops, using border hedgers, all reduces the loss of top soil. How does

deforestation increase the loss of top soil ?

Fertiliser affecting crop yields: Word bank: soil erosion

Fertiliser and soilManure and soilRich soilPoor soilCrop yield in tomatoes


Crop yieldCrop yield fivefive greenhousesgreenhouses


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Crop yieldCrop yieldFruit and vegetables grown intensively in greenhouses have all their environmental conditions

very carefully controlled by farmers. The amount of light, h_____, nutrients, water and even

carbon dioxide can be carefully controlled. Supplying additional lighting, heat or fertilisers allcosts money and can affect the p_______ a farmer makes when they sell their crops.Look at

the five scenarios and work out the profitability of the crop when costs have been deducted.

Explain why spending huge amounts of money does not always increase the yield and profit of

the farmers crop ?

Factors affecting crop yields:

50.00 250.00 300.00 225.00 275.00

______?

225.00

______?

10.00

50.00

50.00

50.00

Scenario 4

______?

300.00

______?

25.00

75.00

50.00

75.00

Scenario 3

______? ______? 50.00Profit

275.00 250.00 50.00Crop sells for

______? ______? 0.00Total cost

10.00 10.00 0.00CO2 costs

50.00 50.00 0.00Fertiliser costs

25.00 25.00 0.00Light costs

100.00 50.00 0.00Heating costs

Scenario 5Scenario 2Scenario 1FactorsGreenhouse crops

Word bank: heat profit


Plant fertilisersPlant fertilisers


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Plant fertilisersPlant fertilisersIntensive farming reduces the quality of the soil, stripping all the essential plant minerals

like n__________, phosphates and potassium. Farmers add fertilisers at the beginning of

every growing season to replace lost minerals. Crop yield increases with the increasingamount of fertilisers added to the soil. Organic farmers only use natural sources of

fertilisers like animal dung or manure. Why is the accumulation of nitrogen in rivers,

ponds and lakes bad for the environment ?

Using fertilisers:

Natural fertilisers used by

organic farmers, consists of

animal waste and composted

vegetable matter. This mineral

rich humus adds the necessaryminerals like nitrogen and

potassium and also improves the

soils quality.

Rendered fertiliser is made by

processing animal carcasses and

bones and subjecting them to

very high temperatures. This

reclaimed bone and animal wasteis heated and ground in some

cases and then sold to farmers to

spread on their fields.

NPK fertilisers contain:

Nitrogen (N) for growth of leaves

and stem.

Phosphorus (P) for healthy roots.

Potassium (K) for health leaves.

Notes

Natural fertiliser

Diagram

NPK fertilisers Rendered fertiliser

Word bank: nitrates


The nitrogen cycleThe nitrogen cycle


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All living organisms require the element n_________ to make proteins. Although air contains

almost 80% nitrogen gas, plants and animals cannot use it in this form.Nitrogen (N2) has to be

changed to nitrates (NO3-

) before plants can absorb and use nitrogen to build proteins. Animalsacquire their nitrogen from plants or animals that feed on plants. The nitrogen cycle shows how

nitrogen gas is changed into nitrates.

The nitrogen cycle:

g yg y

Nitrates (NO3-)in the soil.

Nitrogen fixing

bacteria in root

nodules

Nitrates from

fertilisers &

lightning

Plant and

animal remains

(NH3)

Denitrifying

bacteria in soil

(NH3)

N2 Atmosphere

Soil

Atmosphere

Plant biomassAnimal biomass

The atmosphere is 78% Nitrogen gas.

Lightning

Animal waste Legumes Fertilisers

Word bank: nitrogen


HydroponicsHydroponics


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Hydroponicsy pHydroponics is increasingly being used by farmers to improve the yield and quality of

crops. Using hydroponics means growing plants or crops without s____. The majority of

tomatoes, cucumbers and sweet peppers that you can buy in the supermarkets are grownthis way. There are two techniques used in hydroponics:

1: Peat culture

2: Nutrient film

Hydroponics: Word bank: soil

Tomatoes, sweet peppers

cucumbers and bedding plants,

are all raised using the nutrient

film technique. The quality and

yield is always tightly controlled

by the grower. This allows the

growers maximum prices.

Plants are grown in sterile sand

or a synthetic wool-like material.

The roots of the plants are bathed

in a solution containing oxygen,

plant nutrients and water. At

anytime the level of nutrients can

be altered.

Peat culture is used to grow crops

like tomatoes. Peat taken from

peat bogs is treated before it is

used. It is neutralised using

alkaline and enhanced by adding

nutrients like nitrates, phosphates

and potassium (NPK.)

Notes

Example

Diagram

Peat culture Nutrient film


Greenhouse productionGreenhouse production


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ppFarmers and commercial growers use greenhouses to improve the yield of their c_____

and control when and where crops are grown. Using a greenhouse allows farmers to

control all the growing conditions, so that crops can grow at any time of the year or inareas where they would not normally grow. Although it is more e_________ than just

using a field, the additional income from crops that reach supermarket shelves early on in

the season, or crops that are not normally native to this country outweigh those extra costs.

Glasshouse production: Word bank: crop expensive

During the winter

months, gas burners,

whilst supplying carbon

dioxide gas also raise the

temperature inside the

greenhouse, increasing

the photosynthetic rate.

Temperature

Most greenhouse have

computer controlled

watering systems so that

the soil remains moist to

support plant turgidity

and photosynthesis

during growth.

Pumping carbon dioxide

gas into a greenhouse

can also increase the

rate of photosynthesis.

Normally gas burners

are used to produce

carbon dioxide gas.

Artificial lighting is

used to increase the rate

of photosynthesis and

therefore growth. Plants

can photosynthesize 24

hrs a day inside a

commercial greenhouse.

Notes

Water

Diagram

Light Carbon dioxide


Costs and benefits of intensive farmingCosts and benefits of intensive farming oneone


27/31

ggWithin the twenty five countries of the European Union, farmers grow excess crops, when

compared to what we need. The dramatic increase in crop y______ over the last half

century is due largely to intensive farming techniques. These techniques include thewidespread use of f__________, insecticides, pesticides, greenhouses and hydroponics.

Furthermore, using and selecting the best performing fruit and vegetable varieties

produced by selective breeding has also led to a dramatic increase in the crop yield.

Benefits of intensive farming:Word bank: yields fertiliser

The range of products in

shops has changed in

two ways. (i) Now you

can buy fruit and

vegetables out of season(ii) and from other parts

of the World.

Range of products

Fruit and vegetables

arrive fresh and ready to

eat in our supermarkets

on a daily basis. You can

now buy from all overthe World at any time of

the year.

The quality of foods has

never been better,

because of modern crop

varieties, technology

and the widespread useof fertilisers, pesticides

and insecticides.

Crop yields per hectare

have increased over the

last 50 years. This

means that we now

destroy excess fruit,vegetable and animal

products in Europe.

Notes

Timings

Diagram

Yield Quality


Costs and benefits of intensive farmingCosts and benefits of intensive farming twotwo


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ggFarmers and the European Common Agricultural Policy makes sure that we all have food on our

table, however each family in Europe subsidies farmers to grow crops and raise animals. This costs

us on average up to 1000 per year per family. We have also destroyed n________ habitats to raiselivestock like cattle and grow crops like wheat. Also, the widespread use of insecticides and

pesticides poisons many food chains affecting many native s_________. Furthermore, mechanisation

and the use of crude oil adds to the amount of greenhouse gases and global warming. All this so we

can eat fruit from far away places at anytime of the year. Why should we only eat local produce grow

in season ?

Costs of intensive farming: Word bank: natural species

Excessive use of

fertilisers that enter the

water cycle can cause

widespread damage in

lakes, rivers and ponds

close to agricultural

land.

Fertilisers

The cost of the European

Common Agricultural

Policy (CAP) is a

staggering 1000 per year

for each family. Some of

the food produced is

never sold.

Heating greenhouses,

supplying CO2 gas and

using tractors increases

the use of fossil fuels

like oil. This causes an

increase in atmospheric

carbon and acid rain.

Using only a small

number of fruit and

vegetable varieties as

well as clearing forests

and woodland for

farming reduces global

biodiversity.

Notes

Cost

Diagram

Biodiversity Fossil fuels


Extension questions and homework


29/31

1: Define the following terms: Water-transport, Osmosis, Transpiration, Xylem, Phloem, Active-transport, Minerals,

Organic-farming, Hydroponics & Greenhouse-production.

2: Look at the picture of three types of plant tissue. Complete the table.

3: a) What does a potometer measure in plants.

b) What do xylem tissues transport to the leaf.

b) What do phloem tissues transport around the plant.

c) How is a root hair cell adapted to take in water from the soil.

d) What is the name given to the loss of water from the leaves.

e) What is the name given to water movement through the root cells to the xylem.

f) What is the name given to water movement through the xylem tissue.

Role in transpiration

Leaf

Xylem

Stomata

FunctionPart

Stomata Xylem Leaf


4: Look at the information in the table below. It shows the diameter of the stomata cells over a 24 hr period:


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a) Explain why the diameter changes over this 24 hr period.

b) At midday the light intensity is strongest. How do the stomata cells react to this.

c) At dawn and dusk, is the rate of respiration and photosynthesis the same.

5: a) Other than water and carbon dioxide, plants also need minerals (e.g. phosphates, nitrates and potassium) what are

these minerals used for and how do the plants obtain them.

b) Show how a specialised root hair cell takes in minerals like nitrates from the soil.

c) Do the minerals given in part (a) give any energy value to the plant.

d) Compare those minerals that plants require for healthy growth to the minerals and vitamins we require in our

own diet.

e) Somebody observed that wheat grows taller and gives a higher yield when the field is closer to a coal burning

power station. Suggest a reason for this.f) Explain why grass doesnt need cutting during the winter months when the average daily temperature is below

6oC.

6: Complete the following:

Plants produce ____________ and oxygen during photosynthesis. This all takes place in the chloroplast found in the_______________ cells. The active chemical in the chloroplast is called _____________. It is able to use light

energy to form new chemical bonds between water and carbon dioxide.

0.010.100.200.250.400.400.250.150.10.01Diameter (cm)

22.0020.0018.0016.0014.0012.0010.0008.0006.0000.00Time (hr)


7: a) Plants and crops need mineral salts for healthy growth. Give the name of three of these mineral salts.


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b) A farmer wants to increase his crop yield by using fertilisers. The able below shows how mass of crop produced

from a field depends on the quantity of nitrogen used.

(i) What is the maximum mass of crop that could be produced using nitrogen fertilisers.

(ii) Explain why using 700kg/hectare of fertilisers actually decreases crop yield compared to your answer in part (i).

(iii) Large amounts of fertilisers dissolve in water. When it rains fertilisers can accumulate in rivers and ponds.Explain why this is a problem.

(iv) Some consumers prefer organically grown crops. State two advantages and disadvantages of eating organically

grown crops.

8: a) Explain the difference between peat culture and nutrient film hydroponics.

b) What are the benefits of intensive farming to the (i) farmer and (ii) consumer.

c) What are the disadvantages of intensive farming to (i) the consumer (ii) biodiversity (iii) the environment.

9: Complete the following:

Water passes into the root hair cell by ___________. Mineral salts like _____________ potassium and phosphateare taken up by active transport. A root hair cell has a ____________ surface area to help water and mineral salt

uptake. Water is then transported through the ___________ tubes by capillary action to the leaf tissue. Palisade

cells require water during photosynthesis to manufacture glucose. Water is lost through the leaves thorough the

_____________. They are opened during the day and close at night when no p______________ takes place.

7.5100

14300

13700

16500

15.5400

15126Crop yield (tonnes/hectare)6002000Amount of nitrogen (kg)

Internet:

Go to google.co.uk and find about problems caused by overuse of nitrogen fertiliser. Also find out about the benefits

of organically grown fruit and vegetables.

Science-Interactive.co.Uk_Water Transport in Plants

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