The thylakoid lumen is used for photophosphorylation during photosynthesis. ThoughtCo. A Thylakoid is a membrane-bound compartment inside chloroplasts and cyanobacteria.They are the site of the light-dependent reactions of photosynthesis.The word "thylakoid" is derived from the Greek thylakos, meaning "sac".Thylakoids consists of a thylakoid membrane surrounding a thylakoid lumen… Yusuke Kato, Wataru Sakamoto, in International Review of Cell and Molecular Biology, 2010. She has taught science courses at the high school, college, and graduate levels. While thylakoids in plant cells form stacks of grana in plants, they may be unstacked in some types of algae. The thylakoid consists of the thylakoid membrane and the enclosed region called the thylakoid lumen. [< German Thylakoid (1961) < Greek thȳlakoeidḗs resembling a bag = thylak (os) sack + -oēidēs -oid] Photosystem II uses light to oxidize water to produce molecular oxygen (O2), electrons (e-), and protons (H+). Is similar in structure to NAD but has an extra phosphate group. The lumen of the thylakoid contains proteins used for protein processing, photosynthesis, metabolism, redox reactions, and defense. one of an interconnected stack, having a pigmented membrane that is the site of photosynthesis. Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. Ask Question ... or whether the lumen space is connected to the intermembrane space of the chloroplast. Each granum is identical to a coin stack, with a thylakoid being each “coin.” Some thylakoid membranes extend from one … Digestive System: Mouth and Stomach Another cell type, parietal cells, secrete hydrogen and chloride ions, which combine in the lumen to form hydrochloric acid, the primary acidic component of the stomach juices. It contains chlorophyll, which power the formation of NADPHfrom NADP+ and H+, and enzymesrequired to form ATP, NADPH, or both in photosynthesis. A fluid-filled internal space, the thylakoid lumen, is enclosed by the thylakoid membrane. Helmenstine, Anne Marie, Ph.D. "Thylakoid Definition and Function." Light energy is trapped and used to Bond ADP and Pi to make ATP along with splitting water into … The work of the chloroplast takes place in the stroma, the lumen, and, most importantly, in the thylakoid membrane itself. Its orthologues are found in bacteria archaea, fungi, plants, and animals (Paetzel et al., 2002).SPase I … Nevertheless, dyamic studies reveal a normal lipid bilayer organisation in thylakoid … a structure in the chloroplast of photosynthesizing cells, usu. Thylakoid extent can change within minutes of light exposure or removal. It can refer to: The interior of a vessel, such as the central space in an artery, vein or capillary through which blood flows. Arabidopsis encodes 16 DEGP-like proteases, and four of these appear to be targeted to the chloroplast and located in the thylakoid lumen (DEG1, DEG5, and DEG8) or peripherally attached to the stromal side of the thylakoid membrane (DEG2) (Peltier et al., 2002; Schubert et al., 2002). a flattened sac or vesicle lined with a pigmented membrane that is the site of photosynthesis, in plants and algae occurring in interconnected stacks constituting a granum of the chloroplast, and in other photosynthesizing organisms occurring either singly or as part of the cell membrane or other … The increase in proton concentration in the lumen mediates the decrease of pH. one of an interconnected stack, having a pigmented membrane that is the site of photosynthesis. It is the site that contains the chlorophyll used to absorb light and use it for biochemical reactions. Photosynthetic pigments (e.g., chlorophyll) are embedded into the thylakoid membrane, making it the site of the light-dependent reactions in photosynthesis. a structure in the chloroplast of photosynthesizing cells, usu. ... Is lumen space of a thylakoid completely separate from the intermembrane chloroplast space? The protein plastocyanin is an electron transport protein that transports electrons from the cytochrome proteins to Photosystem I. Cytochrome b6f complex is a portion of the electron transport chain that couples proton pumping into the thylakoid lumen with electron transfer. Although oxygen is needed for cellular respiration, the gas produced by this reaction is returned to the atmosphere. The net result is a low pH in the thylakoid lumen, and a high pH in the stroma. A saclike membrane in the chloroplasts of plant cells that is often arranged in stacks called grana and that is the site of the light reactions of photosynthesis. 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