Celluar Respiration/Photosynthesis Flashcards - …
()THE accepted pathway of CO2 fixation in plant photosynthesisrequires that the photosynthetic light reactions produce ATP and reducedpyridine nucleotide (NADPH) in the molar ratio 3:2 (ref.
Study Flashcards On Celluar Respiration/Photosynthesis ..
Photophosphorylation is the production of ATP using the energy of sunlight. Photophosphorylation is made possible as a result of chemiosmosis. Chemiosmosis is the movement of ions across a selectively permeable membrane, down their concentration gradient. During photosynthesis, light is absorbed by chlorophyll molecules. Electrons within these molecules are then raised to a higher energy state. These electrons then travel through Photosystem II, a chain of electron carriers and Photosystem I. As the electrons travel through the chain of electron carriers, they release energy. This energy is used to pump hydrogen ions across the thylakoid membrane and into the space within the thylakoid. A concentration gradient of hydrogen ions forms within this space. These then move back across the thylakoid membrane, down their concentration gradient through ATP synthase. ATP synthase uses the energy released from the movement of hydrogen ions down their concentration gradient to synthesise ATP from ADP and inorganic phosphate.
During carbon fixation, carbon dioxide in the stroma (which enters the chloroplast by diffusion) reacts with a five-carbon sugar called ribulose bisphosphate (RuBP) to form a six-carbon compound. This reaction is catalysed by an enzyme called ribulose bisphosphate carboxylase (large amounts present within the stroma), otherwise known as rubisco. As soon as the six-carbon compound is formed, it splits to form two molecules of glycerate 3-phosphate. Glycerate 3-phosphate is then used in the reduction reactions.
The Process of Photosynthesis | Chlorophyll | Photosynthesis
• Sulfur Dioxide (SO2) – Sixty percent of sulfur dioxide comes from coal burning for electricity and home heating while 21 percent comes from refining and the combustion of petroleum products.
• Ozone (O3) – Ozone is a naturally occurring oxidant that exists in the upper atmosphere. O3 may be brought to Earth by turbulence during severe storms. Also, small amounts are formed by lightning. Automobile emissions and industrial emissions mix in the air and undergo photochemical reactions in sunlight releasing ozone and another oxidant, peroxyacetylnitrate (PAN). Naturally, high concentrations of these two oxidants build up where there are many automobiles.
• Nitrogen Oxides (NOx) – Probably the largest producer of nitrogen oxide is automotive exhaust. These are also formed by high temperature combustion when two natural air components are present; nitrogen and oxygen.
• Particulates – These are small particles emitted in smoke from burning fuel, particularly diesel, which enters our lungs and causes respiratory problems. With trees present, there is up to a 60 percent reduction in street-level particulates.
Plants make their own food thru the process of photosynthesis
I should point out that both the photo and the synthesis parts of photosynthesis aremultiple step reactions. Quite a number of steps are involved in separating hydrogen andelectrons from oxygen in water. Similarly, quite a number of step are involved in removingoxygen from carbon dioxide and incorporating hydrogen and additional electrons into thecompound. Also, the carbon dioxide is not used to create a new compound as such, butinstead, the carbon is incorporated into existing carbon-containing compounds in a waythat makes them larger than they were before.
Oxygen reduction reaction thesis | 3 Rivers Archers
Immediatelyafter exposure to 14CO2, the plant's photosynthetic tissue iskilled by immersing it in boiling alcohol, and all of the biochemical reactions cease.