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1. Slide 1: Science Interactive LTD Copyright 2005 Science Interactive LTD Multimedia CD-ROM for PC is a collection of 38 units totalling over 1150 PowerPoint slides matched to current single and double Science GCSE syllabuses. 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 and questions. Units can be used in the classroom via an interactive whiteboard, data projector or used during individual study via a PC or school network. Full users’ licence is available under our ‘comprehensive package’ or lessons can be purchased separately. Science Interactive LTD. PO BOX 50764 LONDON NW6 9AT email: sales@science-interactive.co.uk web: www:science-interactive.co.uk GCSE SCIENCE Unit 1: The Digestive System Unit 20: Crude Oil and its Products Unit 2: The Circulatory System Unit 21: Rock Cycle OCR Unit 3: Healthy Body and Immunity Unit 22: Elements, Molecules and Compounds EDEXCEL AQA Unit 4: The Respiratory System Unit 23: Ionic and Covalent Compounds Unit 5: Nervous System and the Senses Unit 24: The Halogens, their Uses and Compounds Unit 6: Human Homeostasis Unit 25: The Noble Gases, their Properties and Uses Unit 7: Hormones and the Endocrine System Unit 26: Rates of Reaction Unit 8: Drugs and Bad Body Maintenance Unit 27: Energy Unit 9: Photosynthesis in Green Plants Unit 28: Generating Electricity and its Domestic Use Unit 10: Water Transport in Plants Unit 29: Electricity Unit 11: Flow of Energy and Elements through the Environment Unit 30: Light and the Electromagnetic Spectrum Unit 12: Mitosis and Meiosis Unit 31: Radioactivity Unit 13: Inheritance and Selection Unit 32: Newton's Forces and the Effects of Forces Unit 14: Evolution and Human Impact Unit 33: Earth and Space Unit 15: Genetic Engineering Unit 34: The Earth and Plate Tectonics Unit 16: The Periodic Table and its Elements Unit 35: The Alkaline Earth Metals Unit 17: The Alkali Metals Unit 36: Sound and Hearing Unit 18: Metals and their Properties Unit 37: Natural Forces Unit 19: The Transitional Metals Unit 38: Cells, Tissue, Organs and Organs systems
2. Slide 2: Science Interactive LTD Copyright 2005 Unit 9  Photosynthesis in Green Plants 
3. Slide 3: Unit 9: Photosynthesis in Green Plants Science Interactive LTD Copyright 2005 Understand: Keywords: The anatomy and cell parts of the common plant 1. Leaf, Tissue, Organ, Cell, Palisade, cell. Photosynthesis, Substrates, Water, Carbon The role of the chloroplast and mitochondria 2. dioxide, Products, Glucose, Oxygen, Light, during photosynthesis and respiration. Energy, Intensity, Limiting, Factors, Light, The role of the leaf and the palisade cell during 3. Temperature, Colour, Rate, Tropism & Stimuli. photosynthesis. That the substrates for photosynthesis are water 4. and carbon dioxide. That the products of photosynthesis are glucose 5. and oxygen. That light energy is essential for photosynthesis 6. to occur. That the overall rate of photosynthesis is 7. determined by limiting factors including carbon dioxide, light intensity, light colour and temperature. That plants use glucose to make other 8. molecules. That plants can respond to stimuli like light, 9. gravity and moisture. Click mouse to begin Science Interactive LTD PO BOX 50764 LONDON NW6 9AT web: www.science-interactive.co.uk email: sales@science-interactive.co.uk
4. Slide 4: Science Interactive LTD Copyright 2005 Levels of organisation in plants In plants, as in animals, similar cells performing similar f__________ are organised into tissues. Leaf palisade tissue consists of identical palisade cells functioning together to enable photosynthesis to occur. Other tissues found in green l________ also support photosynthesis. A leaf is an organ made up of many different tissues. Different organs work together as part of the entire plant organism. There are four distinct organs in a typical plant: The root system, the stem system, the leaf system and the reproductive system. Name the function of each of the four organ systems found in green plants ? Cells, tissues, organs and organ systems in plants: Word bank: functions leaves Cells Tissues Organs Organism Diagram Cells are highly Tissues like the palisade Organs are a collection The are four organ Notes specialised and are layer or stomata tissue of tissues like the leaf. systems that support life designed to do their job are a collection of cells Many separate organs in plants. All perform within the plant. List 3 working together to build an organ system. specific roles. Which of specialised cells found perform specific tasks in List 3 organs in the these systems does not in green plants ? the plant. plant ? support photosynthesis ?
5. Slide 5: Science Interactive LTD Copyright 2005 Plant leaf system A number of cells and tissues within the plant leaf play a role during photosynthesis, whereby water and carbon dioxide combine during photosynthesis to form g_______ and o_________. Palisade cells containing chloroplast are the main site of glucose production. Xylem tissue supplies water from the root and phloem tissue transports glucose made during photosynthesis around the plant. Gaseous exchange during photosynthesis and respiration is controlled by the stomata cells. Why are the stomata cells found only on the underside of the leaf ? Plant leaf system: Word bank: glucose oxygen Stomata cells Xylem tissue Plant leaf Leaf system Diagram A B C E D Stomata found on the The xylem tissue The leaf is a collection The leaf system is a Notes underside of the plant transports water and of tissues: collection of leaves leaf allows gaseous minerals like nitrates that work together A: Upper epidermis exchange and water from the root system to producing glucose and B: Palisade layer transpiration. They open the leaf system via the oxygen from water and C: Spongy mesophyll during the day and plant stem. Phloem carbon dioxide using D: Lower epidermis remain closed during the tubes transport sugary the energy from the E: Stomata night. sap all around the plant. sun during daylight hours.
6. Slide 6: Science Interactive LTD Copyright 2005 Specialised cells in plants Like animals, plants have many different s____________ cells performing different functions. Green plants have many examples of specialised cells that are designed for functions like photosynthesis, growth, reproduction, taking in w______ and minerals from the soil. The leaf palisade cell is a good example of a specialised cell in plants. It is well designed for photosynthesis, for example it contains many chloroplasts organelles, rich in chlorophyll. Where is the palisade tissue located in the plant ? Specialised cells: Word bank: specialised water Palisade cell Root hair cell Stomata cell Pollen cell Diagram Green leaves contain The root hair cell has The stomata cells Pollen cells, normally Notes many palisade cells a large surface area to controls the exchange transferred to the which are rich in volume ratio, so that it of CO2 and oxygen female carpel by bees chloroplasts that can absorb water and and other insects carry during photosynthesis. enable photosynthesis minerals from the soil. genetic information to They close during the to occur. Why do root Name two of these create a new plant night. At what time cells not have these cell mineral salts found when it fuses with the during the day does parts ? dissolved in water ? female ovule. CO2 enter the leaf ?
7. Slide 7: Science Interactive LTD Copyright 2005 The common plant cell Plant cells, like animals cells are made from many cell parts or organelles, each with a specific function. The common plant cell has some similarities and some differences to animal cells. This reflects differences in the way plants and animals feed and support themselves. The most important cell part is green c____________ containing chlorophyll which allows photosynthesis to occur. Common plant cell: Word bank: chloroplast Cell part Function (complete) Nucleus Control cells activities and contains DNA Cytoplasm _______________________ ? Membrane _______________________ ? Vacuole _______________________ ? Cell wall _______________________ ? Chloroplast _______________________ ? Mitochondria _______________________ ? Lysosome _______________________ ?
8. Slide 8: Science Interactive LTD Copyright 2005 Mitochondria and chloroplast organelles If you view plant and animals cells under a microscope, you can see tiny dots in the cytoplasm. These are the mitochondria. Cellular r____________ occurs in the mitochondria, releasing energy from glucose molecules. Plants also have green c____________ containing chlorophyll where water and carbon dioxide are combined to form glucose and o_________ during photosynthesis. Why do muscle cells contain more mitochondria than skin cells ? Mitochondria and chloroplast: Word bank: respiration chloroplast oxygen Mitochondria Chloroplast Diagram Matrix Membrane Matrix Membrane Function in the cell To respire glucose with oxygen To produce glucose using CO2 and water. All providing cell energy. All living cells green plants have these organelles. have these organelles. Equation C6H12O6 + 6O2 6H2O + 6CO2 6H2O + 6CO2 _____ + _____ Animal or plant Animal and plant Plant only
9. Slide 9: Science Interactive LTD Copyright 2005 Plants as producers one Plants are called producers because they produce all the World’s 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 Photosynthesis in action Plant yield Plant yield: (kg per hectare) Diagram C6H12O6 6H2O Chloroplast Glucose Energy 14000 10000 6CO2 6O2 6000 2000 Plant cells <1000 Green chlorophyll contained in Plants only use a small fraction of the sunlight energy, they Notes palisade chloroplasts are able to receive every year. Despite this, sugarcane produces up to use light energy to enable carbon 200 tonnes of glucose per year per hectare. The most dioxide and water to combine to productive areas are the equatorial regions that receive the form glucose and oxygen. most sunlight energy.
10. Slide 10: Science Interactive LTD Copyright 2005 Plants as producers two The glucose produced during photosynthesis in green plants is used to make plant c____________, lipids and proteins. Every year over 70,000,000 kJ of sunlight energy falls on every metre squared of land. Plants only use about 90,000 kJ/m2/year of l_______ energy during photosynthesis, however they produce over 132 billion tonnes per annum of biomass. Overall plant yields depend on a number of factors including light availability, soil quality, rainfall levels and competition. How could you determine the yields of different crops over time ? Plant yield and biomass: Word bank: carbohydrates light Crop Sugarcane Corn Rice Wheat Diagram Sugarcane, rich in Corn, rich in proteins Rice, rich in carbo- Wheat, rich in carbo- Notes glucose can produce a and carbohydrates can hydrates can produce a hydrates and sugars can yield of up to 9000 kg produce a yield of up to yield of up to 3000 kg produce a yield of up to per acre. 5500 kg per acre. per acre 2500 kg per acre.
11. Slide 11: Science Interactive LTD Copyright 2005 Plants as producers three Plants are extremely efficient at transforming the energy carried by light to chemical energy trapped in glucose molecules, which are produced during p_____________. Their efficiency is about 80%, far higher than typical values for herbivores and carnivores. Only a small fraction of the c__________ energy they produce in the form of glucose is lost through respiration or waste. How could you determine the amount of glucose that is used during cellular respiration in plants ? Plants using light energy: Word bank: photosynthesis chemical Plants use of light energy Process Biomass: Energy contained Diagram 8,000 kJ 1 in the tissues of the plant (available for the next level.) Bio Light energy m a ss Respiration: Energy used in 10,000kJ 1 Re 1,500 kJ 2 cellular respiration by all sp ir a plant cells. tio n 2 Wa Waste: Energy contained in ste 500 kJ 3 the waste materials found in 3 leaves. Notes The transfer of energy from the sun’s rays to the glucose found Only a very small fraction of in plant leaves is achieved during photosynthesis. Plants are energy is used for respiration highly adapted and efficient at transforming light energy to or lost as waste. Plants are chemical energy. Over 132 billions tonnes of plant biomass is almost 80% efficient as produced globally every year. producers.
12. Slide 12: Science Interactive LTD Copyright 2005 Plants as producers four Plant leaves contain many palisade cells containing green c___________. Palisade cells use e______ from sunlight during photosynthesis to make g________ and oxygen. This palisade cell layer is found near to the surface of the leaf. Here it can absorb all the sunlight that falls on the leaf’s surface. How could you design an experiment to show that light is an essential factor for photosynthesis ? Plants using light energy: Word bank: chloroplasts energy glucose Anatomy of the plant leaf Process A: Upper epidermis Diagram A B: Palisade layer C: Spongy mesophyll B D: Lower epidermis F E: Stomata G C F: Xylem G: Phloem D Give a function of the leaf tissue. E Say how each part helps photosynthesis ? The transfer of energy from the sun’s rays to the glucose found in Only a very small fraction of Notes plant leaves is achieved during photosynthesis. Plants are highly energy is used for respiration or adapted and efficient at transforming light energy to chemical energy. lost as waste. Plants are almost Over 132 billions tonnes of plant biomass is produced globally every 80% efficient as producers. year.
13. Slide 13: Science Interactive LTD Copyright 2005 Plants as producers five Every tissue found in green leaves, supports the production of glucose during photosynthesis. Palisade cells containing green c___________ have enzymes which use light energy to combine water and carbon dioxide forming glucose and oxygen. The xylem transports w______ from the root. Phloem tubes transport glucose to the rest of the plant. Stomata cells allows carbon dioxide from the atmosphere and promote transpiration. The spongy mesophyll allows carbon dioxide to diffuse quickly to the palisade cells. Why are the palisade cells filled with chloroplast found in the upper part of the leaf ? Plants leaf structure and anatomy: Word bank: chloroplast water Parts of the leaf Cuticle Upper epidermis Palisade layer Spongy mesophyll Lower epidermis Stomata Guard cells Xylem Phloem Give a function for each tissue found in green leaves. Say how each part helps photosynthesis ?
14. Slide 14: Science Interactive LTD Copyright 2005 Photosynthesis and its equation one Photosynthesis, the process whereby l______ energy is used by palisade cells found in green leaves to combine carbon dioxide and water to produce glucose and oxygen. This is the equation for the whole process. Carbon dioxide + Water Glucose + Oxygen Light and chlorophyll From the equation we can see there are three requirements:  Light  Chlorophyll  Substrates: Carbon dioxide and water Requirements for photosynthesis: Word bank: light Light Chlorophyll Carbon dioxide and water Diagram Carbon dioxide Water Light is used to provide the Green chlorophyll found in the Carbon dioxide, absorbed by the Notes energy required during leaf palisade layers uses light leaf and water absorbed by the photosynthesis to combine energy to form glucose and root hair cells are essential water and carbon dioxide oxygen. It contains a very substrates that are used during producing glucose and complicated series of enzymes photosynthesis making glucose oxygen. that act as catalysts. and oxygen.
15. Slide 15: Science Interactive LTD Copyright 2005 Photosynthesis and its equation two From the equation for photosynthesis, we can determine the raw materials required during photosynthesis. Glucose 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: water Substrate Carbon dioxide Water Glucose Oxygen Diagram 6 molecules of CO2 1 molecule of glucose 6 molecules of H2O 6 molecules of O2 Carbon dioxide is Water is taken from Glucose produced Oxygen is taken out Notes taken in during day the soil by the root hair during photosynthesis through the leaf light hours through the cells, through the is transported by the during daylight hours leaf stomata cells from xylem and into the leaf phloem to all parts of and released into the the atmosphere. space. the plant. atmosphere.
16. Slide 16: Science Interactive LTD Copyright 2005 Photosynthesis and its equation three 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 an endothermic reaction is photosynthesis, whereby light e_________ is used to combine water and carbon dioxide to form glucose and oxygen. Energy changes during photosynthesis: Word bank: energy Photosynthesis in green plants Key C6H12O6 O2 6O2 C6H12O6 H2O CO2 6CO2 6H2O Products Net energy taken In this reaction H2O Activation energy in during reaction and CO2 substrates Potential energy are combined in the plant leaf cells using light energy to Substrates produce glucose (C6H12O6) and O2. Progress of reaction
17. Slide 17: Science Interactive LTD Copyright 2005 Photosynthesis and its equation four Sunlight, carbon dioxide, water and g______ chlorophyll are all essential for photosynthesis to take place inside a green leaf. Proving that these are essential, however requires experimentation. A series of experiments were carried out and are summarised in the table below. In brief, plants with no access over 48 hours to sunlight, chlorophyll or carbon dioxide were tested for starch in their l________. For each experiment, complete the results and give an explanation ? Factors required for photosynthesis: Word bank: green leaves 1: No light 2: No chlorophyll 3: No carbon dioxide Diagram Complete Complete Results Show leaf after testing with iodine solution. Starch is shown by a blue - Explanation _________________________ _________________________ black colour when in contact _________________________ _________________________ with iodine. What does this _____________________ ? _____________________? experiment prove ?
18. Slide 18: Science Interactive LTD Copyright 2005 Limiting factors for photosynthesis From the equation for photosynthesis, we can also determine the limiting factors affecting the r_______ of glucose production in green leaves. The rate of photosynthesis speeds up as light intensity increases, but only up to a point. The overall rate may also be limited by the concentration of carbon dioxide, the temperature or even the colour of light. Factors that can affect the rate of photosynthesis are called limiting factors. Limiting factors: Word bank: rate Light intensity Temperature CO2 Concentration Colour of light Diagram Equation 6CO2 + 6H20 C6H12O6 + 6O2 Carbon dioxide water light and chlorophyll Glucose Oxygen Light from the sun is The higher the The greater the Red and blue light are Notes used to provide the temperature the more concentration of CO2 absorbed by plants, energy required to often H2O and CO2 whereas green light is the greater the rate of combine H2O and CO2 reflected and not used molecules collide into photosynthesis in green during photosynthesis. during photosynthesis. each other. plants.
19. Slide 19: Science Interactive LTD Copyright 2005 Limiting factors light intensity one During photosynthesis, molecules of water and carbon dioxide collide, form new chemical bonds producing glucose and oxygen. The energy required to form these new bonds in glucose is provided by light energy. The rate of p____________ increases when the amount of light energy increases, but only up to a point. Other factors, like carbon dioxide concentration and temperature also affect the overall rate of photosynthesis. These are called limiting f__________. The factor in shortest supply will always be the limiting factor. Affect of light intensity on the rate of photosynthesis: Word bank: photosynthesis factors Oxygen Oxygen Oxygen Time Experiment 1 2 3 bubbles at bubbles at bubbles at (seconds) 0.1m 0.2m 0.3m Distance (m) 0.1m 0.2m 0.3m 30 23 11 3 Diagram 60 45 22 7 90 67 32 12 0.1m 0.2m 0.3m 120 109 45 17 150 134 65 22 180 157 76 27 210 189 88 32 1: Plot a graph of distance (m) versus rate of oxygen production ? 240 210 109 37 2: Is there a relationship between light intensity and rate of photosynthesis ? 3: What is this relationship ? 270 245 123 42 4: What are the other limiting factors in this experiment ? 5: How could you test out you answer for question 4 ? 300 269 134 45 6: Why is important to control the temperature of the water ?
20. Slide 20: Science Interactive LTD Copyright 2005 Limiting factors light intensity two During the night, no photosynthesis takes place, just plant respiration. At dusk and dawn when the light intensity is low, the rate of respiration and photosynthesis are roughly the same. During the day, when there is greatest l______ energy, there is a net production of glucose and oxygen. The stomata cells, found on the underside of the leaf open 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. Affect of light intensity on stomata opening and closing: Word bank: light Diagram Night Night Dawn Daylight Dusk Glucose Body temp CO2 Microbe Use Oxygen normal 37oC hrs 12pm 8pm14 0 12am 2 4 am 8 6 time days 8 10 12 12am Notes Open Closed Closed
21. Slide 21: Science Interactive LTD Copyright 2005 Limiting factors CO concentration 2 The rate of photosynthesis increases when the concentration of carbon dioxide increases, but only up to a point. Other factors, like l______ intensity and temperature also affect the overall rate of photosynthesis in green plants. These are called limiting factors. The factor in shortest supply will always be the limiting factor. Affect of CO2 concentration on the rate of photosynthesis: Word bank: light Experiment 1 2 3 Oxygen Oxygen Oxygen Time bubbles at bubbles at bubbles at (seconds) CO2 (%) 0.1% 0.25% 0.5% 0.1% CO2 0.25% CO2 0.5% CO2 Diagram 30 19 31 43 60 38 54 65 0.1m 0.1m 0.1m 90 68 101 134 120 102 167 201 150 140 223 256 180 180 324 378 0.1% CO2 0.25% CO2 0.5% CO2 210 230 430 498 240 256 489 578 1 :Plot a graph of CO2 concentration (%) versus rate of oxygen production ? 2: Is there a relationship between CO2 (%) concentration and the rate of 270 298 545 645 photosynthesis ? 3: What is this relationship ? 300 323 595 702 4: What are the other limiting factors for this experiment ?
22. Slide 22: Science Interactive LTD Copyright 2005 Limiting factors temperature The rate of photosynthesis in green plants increases when temperature is increased, but only up to a point, due to other limiting factors like carbon dioxide concentration and light intensity. This is because the two substrates; water and carbon dioxide have a higher kinetic energy, therefore colliding more often and with greater f_______ inside the palisade cell chloroplasts. Very high temperatures stop photosynthesis altogether. This is because, like other enzyme catalysed processes, plant enzymes are denatured when subjected to very high temperatures. Affect of temperature on the rate of photosynthesis: Word bank: force Oxygen Oxygen Oxygen Time Experiment 1 2 3 bubbles at bubbles at bubbles at (seconds) Temp (oC) 25oC 35oC 45oC 25oC 35oC 45oC Diagram 30 19 38 2 60 38 70 3 90 68 128 4 0.1m 0.1m 0.1m 120 102 189 7 150 140 287 11 180 180 356 15 25 C 35 C 45 C o o o 210 230 456 19 1: Plot a graph of temperature (oC) versus rate of oxygen production ? 240 256 502 22 2: Is there a relationship between temperature and rate of photosynthesis ? 3: What is this relationship ? 270 298 615 25 4: What are the other limiting factors ? 5: Why, when the temperature was increased to 45oC in expt 3, was the rate of 300 323 689 32 photosynthesis very low ?
23. Slide 23: Science Interactive LTD Copyright 2005 Limiting factors colour of light The rate of photosynthesis can also be affected by the colour of light. This is because green chlorophyll absorbs r____ and b_____ light and reflects green. When green light is reflected, the light energy is not available to the chloroplasts during the formation of g__________ and oxygen from carbon dioxide and water. Why are many of the seaweeds found deep below the water’s surface red ? Affect of light colour on the rate of photosynthesis: Word bank: red blue glucose White Blue Green Red light Expt. 1 2 3 4 Time light at light at light at at 25oC (seconds) Colour White Blue Green Red 25oC 25oC 25oC of light 30 19 10 4 5 Diagram 60 38 20 6 11 90 68 34 10 24 White Blue Green Red 120 102 49 12 35 150 140 67 16 48 180 180 100 19 60 210 230 120 24 89 1: Plot a graph of colour of light versus rate of oxygen production ? 2: Is there a relationship between colour of light and rate of photosynthesis ? 3: What is this relationship ? 240 256 130 30 99 4: What are the other limiting factors ? 5: Why is the rate of photosynthesis not zero for green light ? 270 298 140 35 123 6: Show in a diagram using a green plant leaf, what colours are absorbed and reflected during photosynthesis ? 300 323 159 42 134
24. Slide 24: Science Interactive LTD Copyright 2005 Plant use of glucose general overview During photosynthesis in green plants, only glucose (C6H12O6) is manufactured. This glucose is then used by green plants for a number of uses including respiration, fruit production, g________ and repair. Plants are able to take a simple molecule like glucose and manufacture all the other types of molecules, including enzymes, l________, proteins and carbohydrates. They really are food factories and essential to all other animal life. Why is the word producers a good term to use when describing plants ? Affect of light intensity on the rate of photosynthesis: Word bank: growth lipids Respiration Diagram Light energy Respiration 6H2O C6H12O6 Mitochondria Energy 6O2 6CO2 Cells Photosynthesis Growth & reproduction Assimilation 6H2O C6H12O6 Chloroplast Light energy 6O2 6CO2 Cells Notes During the day there is a net production of glucose and oxygen by plants as the result of photosynthesis. This glucose is then used during respiration or assimilated and used in the manufacture all the other molecules like proteins, carbohydrates and lipids.
25. Slide 25: Science Interactive LTD Copyright 2005 Plant use of glucose reproduction Pollination is the transfer of pollen, the male sex cells from the a_________ of the stamen by b____ or insects to the surface of the female c_________. Once the pollen sex cells have landed on the female carpel, pollination has been achieved. Flowering plants contain both female and male reproductive organs and can either self or cross pollinate. Following fertilisation, where the ovule and pollen cell fuse, the seed begins to develop surrounded by the swollen ovule which forms the f_______. It is the function of the fruit to disperse the seed. What is this organ’s role in the plant life cycle ? Plant reproductive system: Word bank: anther bees carpel fruit Pollen cells Female carpel Male anther Reproductive system Diagram Pollen, the male sex The egg cells or ovules The stamen is the plant Flowering plants have Notes cells contain the contain the maternal male reproductive organ both male and female paternal genes and are genes and are held in the which contains many reproductive organs. held on the anther which ovule, part of the female millions of microscopic Plants can self or cross is part of the male carpel. pollen cells. pollinate. stamen.
26. Slide 26: Science Interactive LTD Copyright 2005 Plant use of glucose fruits and tubers It is the function of the fruit to disperse the seed. Fleshy fruits like apples, pears, oranges and tomatoes contain lots of sugar as a reward for a_________ and insects. These animals and insects, by eating fruit containing seeds, help spread the seeds prior to g_____________ during the following spring. Also roots tubers swollen with carbohydrates, like those found in carrots, turnips and potatoes act as a food reserve for new growth in the following spring. The sugar or carbohydrates contained in the fruit or root tubers is made during photosynthesis and is transported by the phloem tubes from the leaf. Plant fruits and tubers: Word bank: animals germination Apples Oranges Potatoes Carrots Diagram Notes Fruits, root vegetables and nuts all contain sugar or carbohydrates made from sugar produced during photosynthesis. These plant products all contain stored chemical energy which animals then eat, digest and assimilated into their own bodies. Without plants, there would be no food chains and no oxygen, another product of photosynthesis.
27. Slide 27: Science Interactive LTD Copyright 2005 Tropisms in plants one Plants can respond to environmental stimuli like light, gravity and water. Unlike humans and other animals, plants cannot move themselves because they lack a skeletal m________ system. Plants can, however grow towards or away from a light source. Plant shoots grow towards the light, whereas plant roots grow towards gravity and moisture. If you germinated a seed in space with zero gravity, what would the growth response of the root be like ? Plant reproductive system: Word bank: muscle Growing towards the light Response to light in plant shoots Auxin accumulates on the dark side of the shoot causing cell elongation and the subsequent bending of the shoot towards the light source In the picture above, the tree clearly grows towards the primary source of light. Plants respond to light by using a hormone called auxin. Auxin causes cell elongation and is broken down by sun light. The non-illuminated side therefore elongates bending the shoot towards the sunlight. If the sun is overhead, the shoot continues to grow in an upwards direction. Why do we germinate seeds in the dark ?
28. Slide 28: Science Interactive LTD Copyright 2005 Tropisms in plants two Plants must grow in one direction or another to respond to stimuli like light, moisture or even gravity. They can’t simply m_______ because thy don’t have a nervous or muscle system. The following experiments help us understand the role auxin plays in controlling a plant’s response. Look at the three different scenarios and predict where auxin is found and how this affects plant growth ? Plant reproductive system: Word bank: move Scenario one Scenario two Scenario three Diagram The shoot responds to the light The tip of the shoot is covered The bottom of the shoot is Notes by growing towards the light. with foil. Auxin is present on covered. The tip of the shoot Auxin is found on the dark side both sides and in equal amounts. where auxin is found is still able (right hand side) and causes cell The shoot continues to grow to respond to the light stimulus, elongation. upwards. by growing towards it.
29. Slide 29: Science Interactive LTD Copyright 2005 Extension questions and homework 1: Define the following terms: Photosynthesis, Substrates, Products, Glucose, Oxygen, Limiting factors & Rate- limiting-factors. 2: Look at the diagram of the three types of leaf tissue. Complete the table. Palisade cells Stomata Xylem tubes Tissue Function the in the green leaf How is it specialised Stomata Xylem Palisade cells 3: Answer the following: a) How does water and carbon dioxide arrive at the palisade cell for photosynthesis. b) How is sugar transported around the plant. c) Sugar is also used by all plant cells during respiration to produce energy for life processes in the plant. Compare photosynthesis and respiration. d) During the day do plants respire. e) How could you prove your answers in part (c) by performing an experiment. Explain all the steps. f) Explain why the leaf cuticle is transparent. What other role does the cuticle play.
30. Slide 30: Science Interactive LTD Copyright 2005 4: Look at the information in the table below. It shows the diameter of the stomata cells over a 24hr period: Time (hr) 00.00 06.00 08.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 Diameter (cm) 0.01 0.1 0.15 0.25 0.40 0.40 0.25 0.20 0.10 0.01 a) Explain why the diameter changes over this 24hr 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 doesn’t 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.
31. Slide 31: Science Interactive LTD Copyright 2005 7: a) Plants and crops need mineral salts for healthy growth. Give the name of three of these mineral salts. 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. Amount of nitrogen (kg) 0 100 200 300 400 500 600 700 Crop yield 6 7.5 12 14 15.5 16 15 13 (tonnes/hectare) (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 phosphate are 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. Internet: Go to google.co.uk and find out about fertilizers and how they provide essential minerals for healthy plant growth. Look at how the fertilizers are rated (N:P:K value) and what role each mineral plays in healthy plant growth.