Term 1 - 13 Photosynthesis PDF

MODES OF NUTRITION AUTOTROPHS, HETEROTROPHS & SAPROTROPHS  AUTOTROPHS Autotrophic mode of nutrition- they make their own food with the help of photosynthesis is autotrophic mode of nutrition. eg green plants.  HETEROTROPHS Heterotrophic m...

MODES OF NUTRITION AUTOTROPHS, HETEROTROPHS & SAPROTROPHS  AUTOTROPHS Autotrophic mode of nutrition- they make their own food with the help of photosynthesis is autotrophic mode of nutrition. eg green plants.  HETEROTROPHS Heterotrophic mode of nutrition- th mode in which they cannot make their own food and depend on autotrophs for their food is heterotophic mode of nutrition.eg animals, non green plants. MODES OF NUTRITION OF PLANT PHOTOSYNTHESIS  PHOTOSYNTHESIS From the Greek PHOTO = produced by light SYNTHESIS = a whole made of parts put together. Definition: PHOTOSYNTHESIS is the process whereby plants, algae, some bacteria, use the energy of the sun to synthesize organic compounds (sugars) from inorganic compounds (CO2 and water).  PHOTOSYNTHESIS WHY IS PHOTOSYNTHESIS SO IMPORTANT? PHOTOSYNTHESIS is one of the most important biological process on earth! Provides the oxygen we breathe Consumes much of the CO2 Food Energy Fibers and materials  PHOTOSYNTHESIS GENERAL FORMULA FOR PHOTOSYNTHESIS Oxygen on earth allowed for the evolution of aerobic respiration and higher life-forms. Respiration: extracting energy from compounds (sugars)  ACCESSORY PIGMENT Accessory pigments like chlorophyll and carotenoids (beta-carotene, lycopene): absorb light at different wavelengths, (extending the absorption range) protect cell from harmful byproducts CHLOROPLAST Chloroplasts absorb sunlight and use it in conjunction with water and carbon dioxide gas to produce food for the plant.  LIGHT REACTION Light dependent Occur in the thylakoid membrane of chloroplast Water is split into oxygen gas (O2) and H+ Use light energy (photons) to generate two chemical energy compounds: ATP & NADPH  DARK REACTION Light independent (can occur in light or dark; some enzymes require activation by light) Occur in the stroma of chloroplasts Use the chemical energy produced in Light Reactions (ATP; NADPH) to reduce CO2 to carbohydrate (sugar). CO2 is converted to sugar by entering the Calvin Cycle RESPIRATION, ENERGY AND CARBON CYCLE RESPIRATION ENERGY  ENERGY Newton’s First Law of Thermodynamics: “Energy cannot be created or destroyed, it can only be transformed from one form to another” Once a cell has used energy to do work, it cannot be used again by any organism.  ENERGY ENERGY FLOW IS LINEAR Sun → Earth → Producers → 1st consumers → 2nd consumer heat resp, heat resp, heat resp, heat Energy flows into ecosystem from the sun Energy travels in a straight line by way of food chains CARBON CYCLE  CARBON CYCLE Carbon moves from atmosphere to plants to animals and back to atmosphere. NEXT TOPIC: REVIEW FOR TERM TEST