logging in or signing up BIOLOGY : CHAPTER 6-NUTRITION SOFEss Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Copy Does not support media & animations WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 762 Category: Education License: All Rights Reserved Like it (1) Dislike it (0) Added: October 08, 2011 This Presentation is Public Favorites: 2 Presentation Description by: CHE KU HAFIZA , AHLU ALSALAF ALSALIH, FATIN NORZUHAIRAH, NORDIYANA, SI CHUN SIANG, RASYIDAH & TAN SHU YI Comments Posting comment... Premium member Presentation Transcript Slide 1: CHE KU HAFIZA BINTI CHE KU AMRAN AHLU ALSALAF ALSALIH BIN ABU YAZID FATIN NORZUHAIRAH BINTI MISWAN NORDIYANA BINTI HISBULLAH SI CHUN SIANG RASYIDAH BINTI IZAN TAN SHU YI Slide 2: CHAPTER 6 NUTRITION 6.10 PHOTOSYNTHESIS 6.11 THE MECHANISM OF PHOTOSYNTHESIS 6.12 THE FACTORS AFFECTING PHOTOSYNTHESIS Slide 3: SUBTOPIC 6.10 PHOTOSYNTHESIS Slide 4: WHAT IS PHOTOSYNTHESIS? photo =light Photosynthesis is the process that plants undergo in order to transform solar energy into chemical energy stored in the bonds of sugar molecules PHOTOSYNTHESIS EQUATION Carbon Dioxide Gas Sunlight Water Oxygen Gas Chloropyhll Glucose Slide 5: JAN INGENHOUSZ ARISTOTLE Concluded that soil had the ability to convert dead organic matter into useful nutrients which were absorbed by plants. Concluded that plants had grown mainly from the water which was added regularly and not the soil. Concluded that green plants could restore oxygen and were capable of supporting combustion and respiration. Recognised the importance of sunlight and chlorophyll in photosynthesis. ARISTOTLE DISCOVERY OF PHOTOSYNTHESIS JEAN BAPTISTE VAN HELMONT JOSEPH PRIESTLEY Slide 6: Found that carbon dioxide was taken in by plants during photosynthesis. Showed that water is required during photosynthesis. Recognised that plants convert solar energy into chemical energy during photosynthesis. Discovered that photosynthesis involves in two principal reactions. Proved that chloroplasts were able to produce oxygen by splitting water molecules in the absence of carbon dioxide. JEAN SEN EBIER DE SAUSSURE ROBERT MAYER BLACKMAN ROBERT HILL Slide 7: lamina Guard cell Cuticle LEAF STRUCTURE Slide 8: FUNCTION OF LEAF STRUCTURE Leaves are the main photosynthesis organs of a plant which adapted to carry out photosynthesis efficiently. The leaves grow so that they overlap each other as little as possible.This arrangement called a leaf mosaic which enables leaves to receive as much light as possible. Plants can detect the direction of light so that their leaves are always absorb the maximum amount of light. A leaf consists of a flat, thin lamina which is joined to the stem by a petiole. Xylem transports water absorbed and phloem transports organic product. Both the upper and lower surfaces of a leaf consists of a protective layer of epidermis. The outer surface of both epidermis is coated by cuticle,which helps prevent excessive water loss. The epidermis of a leaf has tiny pores called stomata which flanked by guard cell Inside a leaf are a few layers of cell collectively called mesophyll. In the leaves of dicotyledons,the mesophyll can be divided into Palisade mesophyll Spongy mesophyll Slide 9: ADAPTATION OF LAND PLANTS DESERT PLANTS CACTUS AQUATIQ PLANTS HYDRILLA HIBISCUS WATER LILY LAND PLANTS FLOATING PLANTS ADAPTATION OF PLANTS Slide 10: ADAPTATION OF DESERT PLANTS More stomata on the lower epidermal layer than on the upper epidermal layer Shiny layer of wax covers the epidermis Translucent layer of epidermis High chloroplast density in the palisade mesophyll layer that faces the sun FERN ADAPTATION OF LAND PLANTS Network of veins within the leaf Slide 11: ADAPTATION OF DESERT PLANTS CACTUS Leaves in the form of needles/thorns Have succulent stems Have fewer stomata on their stems Stomata are sunken into the epidermis Have green stems Waxy and thick cuticle covers the epidermis Slide 12: NYMPHAE Waxy cuticle covers the upper epidermis Transparent layer of epidermis cells Palisade layer have a lot of chloroplast Leaf tissues are full of air spaces Have flat leaves All stomata located only on the upper epidermis ADAPTATION OF FLOATING PLANTS Slide 13: No stomata Many small leaves Very little or no cuticle on outer surface of epidermis Tissues full of air spaces ADAPTATION OF AQUATIQ PLANTS HYDRILLA Slide 14: SUBTOPIC 6.11 MECHANISM OF PHOTOSYNTHESIS Slide 15: STRUCTURE OF CHLOROPLAST • known as starch granules • act as a temporary storage place for glucose • the membranous structures that form the grana • each thylakoid consists of a flattened sac enclosing a narrow intra thylakoid space semi-permeable membrane • colourless gel-like matrix • enzymes responsible for dark reaction are found here • starch grains are also found here • site where dark reaction occur • membranous structures that are piled up into stacks like a stack of pancakes • contain chlorophyll to trap sunlight situated in a gel-like matrix called stroma • site where light reaction occur semi-permeable membrane Slide 16: FIRST STAGE OF PHOTOSYNTHESIS LIGHT REACTION Chlorophyll captures light energy Light energy is used to split the water molecules into hydrogen ions, H + The hydroxyl ion then donates its electrons to the chlorophyll that had loses its electron just now to become hydroxyl groups. Excites the electrons of chlorophyll molecules to higher level energy so that it can leave the chlorophyll molecules The electrons that leave the chlorophyll molecules then combine with the hydrogen ion to produce hydrogen atom which will be used in the dark reaction. 1 2 3 4 5 6 This hydroxyl groups will combine each other to form water and oxygen. hydroxyl ions, OH _ Slide 17: DARK REACTION Carbon dioxide is absorb through the stomata 1 2 3 Reduction of carbon dioxide into glucose occur. 4 5 Glucose is then condensed into starch to be stored temporarily in the starch grain until it is needed. Formation of starch is necessary : - Presence of glucose will cause high level of cell osmosis pressure - Starch is insoluble, thus didn’t effect the osmosis of water. SECOND STAGE OF PHOTOSYNTHESIS ATP and hydrogen atoms that are produced in the light reaction just now then move to the stroma to provide energy and reducing power for the dark reaction. Hydrogen atoms are used to fix carbon dioxide in a series of reactions catalysed by photosynthesis enzymes. Slide 18: LR 24H2O 24H 24OH PHOTOLYSIS OF WATER (splitting of water molecules into chlorophyll light hydroxyl ions, OH hydrogen ions, H SUMMARY OF PHOTOSYNTHESIS PROCESS ( USING CHEMICAL EQUATION ) FORMATION OF HYDROGEN ATOM (by combination of hydrogen ions with the released electron) 24H 24e 24H LR Slide 19: LR 24OH 24e 24OH FORMATION OF HYDROXYL GROUP (by losing one electron from the hyroxyl ion) LR 24OH 12H2O 6O2 FORMATION OF WATER AND OXYGEN GAS (by combination of many hydroxyl groups) Slide 20: DR 6CO2 24H 6(CH2O) 6H2O REDUCTION OF CARBON DIOXIDE INTO GLUCOSE (by the help of hydrogen atom) Carbon Dioxide Gas 6H2O 6CO2 Water Glucose OVERALL PHOTOSYNTHESIS EQUATION Chloropyhll Sunlight Chloropyhll Sunlight C6H12O6 6H2O Oxygen Gas Slide 21: LIGHT REACTION DARK REACTION Day and Night Oxygen and Water Product Of Reaction Glucose and Water Grana Substances Required Not Needed COMPARISON Time Of Reaction Day Site Of Reaction Stroma Carbon Dioxide Water Needed Light Energy Slide 22: SUBTOPIC 6.12 FACTOR AFFECTING PHOTOSYNTHESIS Slide 23: LIGHT INTENSITY CONCENTRATION OF CARBON DIOXIDE The rate of photosynthesis is directly proportional to light intensity up to a certain point. The rate of photosynthesis is directly proportional to the concentration of carbon dioxide up to a certain point. The optimum temperature for conducting photosynthesis varies for different species of plants. FACTORS AFFECTING PHOTOSYNTHESIS Slide 24: TIME SUNRISE MIDDAY SUNSET Changes in the rate of photosynthesis throughout the day MORNING AFTERNOON Maximum rate of photosynthesis RATE OF PHOTOSYNTHESIS THROUGHOUT THE DAY Slide 25: AUTUMN SPRING SUMMER WINTER Highest because of the high temperature and high light intensity Low because trees shed their leaves. High because the temperature is high and moderate Ceases because the below 0°C temperature and shorter daylight RATE OF PHOTOSYNTHESIS IN 4 SEASONS COUNTRIES Slide 26: GREENHOUSE Greenhouse is an enclosed glass house used for growing plants in regulated light intensity, temperature, carbon dioxide concentration and humidity. Greenhouse are widely used in countries with 4 seasons to ensure crop production throughout the year. INCREASING THE PRODUCTIVITY OF CROPS Slide 27: 6.10 PHOTOSYNTHESIS 1. Photosynthesis is the process by which plants use the energy from sunlight to produce glucose from carbon dioxide and water. Oxygen is also formed. 2. People who are responsible in the discovery of photosynthesis: Aristotle (f) de Saussure Jean Baptiste van Helmont (g) Robert Mayer Joseph Priestly (h) Blackman Jan Ingenhousz (i) Robert Hill Jean Senebier 3. Leaves are the main photosynthesis organs of plant which are adapted to carry out photosynthesis efficiently. 4. The leaf structure are as follow: 5. Adaptation of plants in different habitats: Land plants-more stomata on the lower surface of the leaf Floating plants-have large, round and flat leaves Aquatic plants-many small leaves Dessert plants-have sunken stomata 6.11 MECHANISM OF PHOTOSYNTHESIS 1. Photosynthesis occurs mainly in the chloroplast: 2. Stages in photosynthesis: LIGHT REACTION - occur only in the presence of light - reaction occur in the grana of chloroplast - results in oxygen and water - photolysis of water occur DARK REACTION - can occur with or without the presence of light - reaction occur in the stroma of chloplast - results in glucose and water - reaction involve the use of enzymes 3. The photosynthesis equation: light 6H 2 O + 6CO2 > C 6 H 12 O 6 + 6O2 chlorophyll 6.12 FACTOR AFFECTING PHOTOSYNTHESIS 1. The rate of photosynthesis is affected by these factors: Light intensity Concentration of carbon dioxide Temperature You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.