Published on March 7, 2014
Photosynthesis by Mpho Modise
photosynthesis • Is the process by which plants utilise to produce their own food
Why is Photosynthesis important? Where by plants produce their own food All of life is supported by photosynthesis because it begins all food webs and chains It also makes oxygen.
Photosynthesis-starts to ecological food webs!
Photo-synthesis means "putting together with light." Plants use sunlight to turn water and carbon dioxide into glucose. Glucose is a kind of sugar. Only plants can produce or make their own food because they consist of chlorophyll Autotrophs make glucose and heterotrophs are consumers of it.
How do we know that plants make carbohydrates from just carbon dioxide water and light energy? Experiments! • For example: Jan Baptisa van Helmont (1648) planted a willow branch weighing 5 pounds into 200 pounds of soil and then after 4 years the tree weighed 169 lbs. and the soil was still nearly 200 lbs.
Photosynthesis sunlight Carbon dioxide + water glucose + oxygen absorbed by chlorophyll 6CO2 + 6H2O + energy C6H12O6 + 6O2 As can be seen from the equation for photosynthesis, the wood, bark, and root came from water and carbon dioxide.
Plants in Action Check it! What is the process that uses the sun’s energy to make simple sugars?
Plant leaves have many types of cells!
The photograph below is an elodea leaf X 400. Individual cells are clearly visible. The tiny green structures within the cells are chloroplasts this is where photosynthesis happens.
Chloroplasts make the sugars!
Photosynthesis • An anabolic, endergonic, carbon dioxide (CO2) requiring process that uses light energy (photons) and water (H2O) to produce organic macromolecules (glucose). SUN photons 6CO2 + 6H2O C6H12O6 + 6O2 glucose
Plants • Autotrophs: self-producers. • Location: 1. Leaves a. stoma b. mesophyll cells Chloroplast Mesophyll Cell Stoma
Stomata (stoma) • Pores in a plant’s cuticle through which water and gases are exchanged between the plant and the atmosphere. Oxygen (O2) Carbon Dioxide (CO2) Guard Cell Guard Cell
Mesophyll Cell Nucleus Cell Wall Chloroplast Central Vacuole
Thylakoid Thylakoid Membrane Granum Thylakoid Space
Absorption of Chlorophyll Absorption violet blue green yellow orange wavelength red
References • http://colleen_snow.azschool.org/teacher/files/documents/photosynthesis[ 1].ppt • http://www.csun.edu/science/scale/4th_grade/ppt/photosynthesis.ppt • Cambpbell & Reece (2010) biology, eighth edition
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Mpho Modise, University of Johannesburg, South Africa, Department of Geography, Environmental Management and Energy Studies, Department Member. Studies ...
Mpho Modise, Tshwane University of Technology, DEPARTMENT OF GEOMATICS, Department Member. Studies Methodological Domain of Geoprocessing (Geomatics ...
Mpho Modise studies Jurisprudence, Emotion, and Legal Theory.