How does the structure of a chloroplast enable it to build up a concentration gradient of protons?
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Chloroplasts contain structures called thylakoids.\n\nThe thylakoid membrane contains the two photosystems utilized by photosynthesis. Most simply, when light strikes the reaction centers of the photosystems, electrons are released into an electron transport chain. As electrons move through the chain,  protons are pumped from the stroma of the chloroplast to the lumen (inside) of the thylakoid. Since the thylakoid membrane is impermeable to protons, a gradient is eventually built up within the thylakoid. This gradient powers ATP synthesis.
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in cellular respiration, hydrogen ions build up in the intremembrane space of the mitochondria
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these are called the classical "work horses" of plant and aniamal cells respectivly.  Regardless chlorplast is reposnsible the energy conversionin photsysnthesis and mitochondia is used in cell metabolism to provide energy through ATP-ADP energy relationships. Any basic science book would do this and so would a Wikepedia or googlesearch. I woudl suggest you go there to get spsecifics, or try the library in your neighbourhood
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Chloroplasts have a double lipid bilayer - so they are made of lipids.\n\nThey actually have all of the others too (including, oddly enough, nucleic acids)
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Yes, guard cells are the only cells in the cell wall that conating chloroplasts. the reason for this been they help to control the opening and the closing of the stomata (the ope that allows gaseous exchange of CO2 and O2.\nDuring the day there is light so the plants can Photosynthesis as CO2 is used up during photosynthesis theCO2 levels in the guard cells falls. This causes water and  salts to be draged into the guard cells and the guard  cells swell up, thus opening the stomata pore .\nAt night CO2 levels are high as photosynthesis cant take place due tothe absence of light and the CO 2 levels rises so water and salt leave the guard cells and they shrink and thus close the stomata pore.
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Water.\n\nWater donates an electron to the P680 molecule of photosystem II to replace the electron that is lost when a photon of light strikes it.
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chloroplast are only in plant cells, they use photosynthesis to make ATP which is energy for the cell.
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Lol. I did this for homework once. Ok ok ok. I'll help yah out since i'm a pretty cool chickk. I'm not going to spend all day rewording these for you so you're going to have to do that part yourself, k?♥\n\nMitochondria: \nMitochondria are the cells' power sources. They are distinct organelles with two membranes. Usually they are rod-shaped, however they can be round. The outer membrane limits the organelle. The inner membrane is thrown into folds or shelves that project inward. These are called "cristae mitochondriales".\n\nChloroplast:\nA green structure, or organelle, contained in the cytoplasm of plant cells. Chloroplasts are reponsible for the green color of almost all plants and are lacking only in plants that do not make their own food, such as fungi and nongreen parasitic or saprophytic higher plants. The chloroplast is generally flattened and lens-shaped and consists of a body, or stroma, in which are embedded from a few to as many as 50 submicroscopic bodies–the grana–made up of stacked, disklike plates. The chloroplast contains chlorophyll pigments, as well as yellow and orange carotenoid pigments. Chloroplasts are thus the central site of the photosynthetic process in plants. The chloroplasts of algae are simpler than those of higher plants and may contain special, often conspicuous, starch-accumulating structures called pyrenoids.\n\nGolgi Apparatus:\nThe Golgi apparatus (also called a Golgi body, Golgi complex, or dictyosome) is an organelle found in most eukaryotic cells, including those of plants, animals, and fungi. The name comes from Italian anatomist Camillo Golgi, who identified it in 1898. The primary function of the Golgi apparatus is to process proteins targeted to the plasma membrane, lysosomes or endosomes, and those that will be formed from the cell, and sort them within vesicles. Thus, it functions as a central delivery system for the cell. It is part of the endomembrane system.\n\nRough&Smooth Endoplasmic Reticulum:\nThe endoplasmic reticulum or ER (endoplasmic means "within the cytoplasm," reticulum means "little net") is an organelle found in all eukaryotic cells. It is part of the endomembrane system. The ER modifies proteins, makes macromolecules, and transfers substances throughout the cell. Prokaryotic organisms do not have membranous organelles and thus do not have an ER. The basic structure and composition of the ER is similar to the plasma membrane, although it is actually an extension of the nuclear membrane. The ER is the site of the translation, folding, and transport of proteins that are to become part of the cell membrane (e.g., transmembrane receptors and other integral membrane proteins) as well as proteins that are to be secreted or "exocytosed" from the cell (e.g., digestive enzymes).\n\n*The ER consists of an extensive membrane network of tubes and cisternae (sac-like structures) held together by the cytoskeleton.\n\nRough ER:\nThe rough ER, also called granular ER or ergastoplasm (acronyms rER or gER) manufactures and transports proteins destined for membranes and secretion. It is called "rough" because ribosomes present on the cytosolic side of the membrane give it a rough appearance.\n\nSmooth ER:\nThe smooth ER (also known as agranular ER or aER) has functions in several metabolic processes, including synthesis of lipids, metabolism of carbohydrates, and detoxification of drugs and poisons. Enzymes of the smooth ER are important to the synthesis of lipids, including phospholipids and steroids. Among the steroids produced by smooth ER are the sex hormones of vertebrates and the various steroid hormones secreted by the adrenal glands. The cells that actually synthesize and secrete these hormones - in the testes and ovaries, for example - are rich in the smooth ER.\n\nRibosomes:\nRibosomes are responsible for assembling the proteins of the cell. Ribosomal subunits are synthesized by the nucleolus. Depend
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the photosynthesis makes food for the rest of the plant transported by phloem. the movement of a plant towards light is phototropism
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Chemiosmosis refers to the diffusion of protons (hydrogen ions) across a semipermeable membrane.\n\nWhile electrons are being pumped through the electron transport chain within the inner mitochondrial membrane, protons are being pumped across the inner mitochondrial membrane from the matrix to the intermembrane space. This creates a gradient, and since there are more protons in the intermembrane space than in the matrix, protons want to move down their gradient and flow back to the matrix.\n\nThey cannot do this, however, because the inner membrane is impermeable to protons. The only way they can return to the matrix is through the molecule ATP synthase, which is located in the inner membrane. When protons flow through the ATP synthase, ATP is produced.
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At the speed of light... than the chloroplast from the plant turn it into energy
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in mitocondria and chloroplasts there is a series of proteins which 'pass on' electrons to generate energy.  It's called 'electron transport', and is usually discussed in terms of glycolysis and photosynthesis
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Lowest potential well determines the localization of the proton. Putting energy into the system, e.g., by light absorption in photosynthetic proteins, will shift the potential wells with respect to each other and proton transfer ensues. If the last member of the chain has the lowest potential, the proton gets trapped in this well. Efficient proton trans-location is deducible from the occurrence of broad negative bands in the IR difference spectrum because the proton with its large polarizability is lost.
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In plants some of the genes from chloroplasts have transferred to the plant nucleus.  Those proteins translated from those genes need to get back into the chloroplast.  The transit peptide sequence helps move chloroplast proteins made in the cytoplasm to the chloroplast (see the references below for technical papers).  Your 2nd question requires more speculation, but I would argue that chloroplasts are prokaryotic derived, specifically cyanobacteria.  See the Wikipedia link for more details.
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The hydrogen gradient builds up creating a hyper-tonic positive gradient on one side that builds up and pushes the protons/Hydrogen atoms across that then creates energy used to synthesis your adenosinetriphosphate.\nI'm not sure if this is 100 percent right but i but something like it on my test last week. :)
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The simple explanation to explain the two is this: in diffusion, chemicals move down a chemical gradient (ie from a place of high concentration to a place of low concentration, the same way that heat flows from a hot object to a cold object).\n\nSimple diffusion is when a chemical transverses any membranes of it's own accord.  For instance, the brain is sheilded from the potentially toxic material in the blood stream by a layer of lipid-rich cells that line the cerebral blood vessels.  The only things that can get through this barrier are those that have special gates in the cell membranes to allow them through (either by facilitated diffusion or active transport), or if a chemical is sufficiently lipophillic (ie solutble in oil) it will be able to diffuse across the blood brain barrier.  Hence, the majority of psychoactive drugs--which need to cross the blood brain barrier to exert their effects on the CNS--are lipophillic.  Since they are foreign elements that the body is not specifically geared to allow, they can only reach the brain by simple diffusion through the membranes.  Steroid hormones, generally derived from highly lipophilic cholesterol, are likewise able to freely diffuse across the cell membranes without needing protection from hydrophobic interiors of the lipid bilayer membranes.\n\nFacilitated diffusion is when the diffusion down the chemical gradient is made possible by the existance of channels that will allow molecules that cannot cross the membranes alone (either due to size or due to thermodynamically unfavorable interactions with the membrane interior) to cross.  An example is the potassium leak channel in the neuron.  The potassium ion is charged, and hence is only souble in polar solvents like water--it is very thermodynamically unfavorable for it to interface directly with the lipids in the membrane interior.  So channles, with a hydrophilic core allow the ions to diffuse out of the cell while side-stepping thermodynamic issues.\n\nBoth of these types of diffusion need to be distinguished from active transport, where a chemical moves UP a gradient by being coupled with a spontaneous, energy releasing activity (like the hydrolysis of ATP).
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A plasmolyzed cell is a "pickeled" plant cell, meaning that it was placed in a hypertonic solution (high salt or sugar solution compared to the cell itself). If the plant has chloroplasts, one can see all the chloroplasts "balling up" and getting crowded in the small cytosol-cytoplasm space during plasmolysis. If the plant cell is put in a 10% solution (and the cell is 0.9% salt itself in the cytoplasm) then there is a net movement of water from high water in the cytoplasm-cytosol of the cell to the area of lower water concentration in the space between the cell mbn and the cell wall until equilibrium is reached.  This is a form of diffusion called osmosis.  \n\nComparable event happens when an animal cell, like an rbc is put in a hypertonic solution.  RBC becomes dehydrated and shrivelled, a process called CRENATION.\n\nBTW, the solutes also move-diffuse from high conc to low as well (aka dialysis, the diffusion of solutes), meaning they move from high solute-low water, to lower solute, higher water until equilibrium is reached.  But the water effects are greater if the solute concentration is not too high, too hypertonic.