difference between effusion and diffusion?
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diffusion is when one gas mixes with another gas. An example is when you open a bottle of perfume in a room. Eventually the odor will permeate the entire room. That's diffusion.\neffusion is when a gas penetrates through a barrier, either into a container or out of one.  An example is when oxygen gas effuses through the bread bag and the bread inside goes stale.
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The diffusion of gas across a membrane requires that the membrane be wet.  If the wet membrane were on the surface the animal would quickly dry out.  Since the exchange is located deep in a lung there is opportunity for the water to be recovered before exhaling.
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Diffusion is when solutes go from a higher concentration to a lower concentration through a membrane. Osmosis, on the other hand, is when water diffuses through a semi-permeable membrane from a higher concentration to a lower concentration.
419290
the sperm is white becuase of seminal fluid, and if you mean diffusions as ejaculation then more sperms will try to fertillise the egg
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Facilitated diffusion does not consume any energy, but it does require the use of a canal or protein to transport the substrate across the membrane.  Active transport also requires a protien embedded in the membrane for transportaion, but it requires energy.  Passive transport does not require a protein or energy.
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Two things make a difference here. The average distance that an individual particle is likely to move before it bangs into another particle and the speed at which the particles are moving.\n\nBecause the space between particles is so much larger in a gas than in a liquid at the same temperature, the "free path length" is longer in a gas and the diffusing substance is typically able to move further in a given period of time.  Therefore, gases diffuse through gases much more rapidly than liquids through liquids if all else is equal.\n\nFor any given combination, the hot gas or liquid substrate will provide more rapid diffusion compared to the cold one due to particle speed.\n\nYou need to check out Graham's Law of Diffusion if you want to get mathematical about this.
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Diffusion of a Dye in Hot and Cold Water\n\nPurpose:  The purpose of this experiment is to demonstrate the principle of diffusion.  Diffusion is the net movement of particles (atoms, ions, or molecules) from an area of greater concentration to areas of lesser concentration.\n\nMaterials and Methods:  For this experiment, the student will require a projector, two petri dishes, two 150 ml beakers, hot plate, potassium permanganate (purple dye), and a spatula.  Obtain about 50 ml of cold water in one beaker and about 50 ml or boiling water in the other.  Place the petri dishes on the projector and add cold water to one dish and boiling water to the other.  Allow the water in the dishes to become still.  Using the spatula, add a crystal of potassium permanganate to the center of each dish\n\nExperiment:  Observe the experiment for several minutes and note what happens to the purple dye in each petri dish.\n\nConclusion:  Do you observe diffusion in each?\n\nHow does the rate of diffusion differ? \n\nWhy is there a greater rate of diffusion in one
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Diffusion thru semipermeable membrane depends on the concentration..ions will move from high concentration to low concentration.  The difference in charge (low vs. high) will cause a change in electrically voltage (mV), which will open the ion channels so the high concentration of ions will move into the low concentration.
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Osmosis is a special type of diffusion that only water can do.In a area of high water the water will move to a area of low water! Definition is....osmosis is a form of diffusion were water moves from a region of high water concentration to a region of low water concentration across a semi-permeable membrane!
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Facilitated diffusion (or transport) is the diffusion across a membrane which is aided by a membrane protein usually by a channel or pore this allows molecules that cannot pass through the lipid bilayer to enter the cell. The process still occurs down a concentration gradient, like normal diffusion and it requires no energy unlike active transport. For more information you could try looking up passive transport.\n\nI hope this helps
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Difusion is the movement of particles from an area of high concentration to an area of low concentration, until they are apread out evenly.\n\nExamples for diffusion: \nThe alveoli are well adapted for diffusion of gases, \nthey have a large surface area\nthey are moist, so gases can dissolve\nthey have thin walls\nand a good blood supply.\n\nThe small intestine is specialised for absorption. \nIt has: \nA thin lining\na good blood supply\na very large surface area.\n\nOsmosis is the diffusion of water molecules from a dilute solution to a more concentrated solution through a partially permeable membrane.\n\nA partially permeable membrane allows water molecules to pass through, but not solute molecules.\n\nWhen a plant cells are full of water they are turgid.\nThis rigidity or turgour gives the plant support\nCells are able to absorb some substances against a concentration gradient.\n\nActive transport needs energy from respiration. \n\nActive transport....\nNot all sustances pass into cells by diffusion or osmosis. Some substances are absorbed against a concentration gradient. But to do this energy is needed and it comes from respiration. This process is called ACTIVE TRANSPORT.\nExample of active transport are:\nThe uptake of ions by root hair cells from the soil, where they are in very dilute solution;\nthe uptake of sugar molecules into the small intestine;\nthe re-absorbtion of useful ions in the nephrons of the kidneys.
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osmosis is the movement of water across a membrane. \nWikipedia on the subject: \n\n"Osmosis is the diffusion of a solvent through a selectively-permeable membrane from a region of low solute concentration to a region of high solute concentration, or in other words, from a high water concentration to a low water concentration. The higher the solute concentration the lower the water concentration will be. The selectively-permeable membrane is permeable to the solvent, but not to the solute, resulting in a chemical potential difference across the membrane which drives the diffusion. That is, the solvent flows from the side of the membrane where the solution is weakest to the side where it is strongest, until the solution on both sides of the membrane is the same strength (that is, until the chemical potential is equal on both sides)."\n\nin short, if you put the potato in fresh water, the potato cells will burst, because water will enter the cells in an attempt to equalize the concentration of salt, etc. inside the cell to what is outside the cell.. if you put a potato in salt water, the cells will shrink, because water will exit them in an attempt to equalize the concentration of salt in the cell and outside of it. I realy don't know what the temperature of water will affect though.
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Osmosis and diffusion are both passive (do not require energy). They both involove the random movement of molecules from a region of high concentration to a region of low. \nWhen someone sprays perfume into the air, the perfume molecules diffuse around their enviroment, thats why you smell it at the other side of the room after a few seconds.\n\nThe differences are that osmosis is the movement of Water molecules from a high concentration to a low concentration through a semi permeable membrane.
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Not sure what you mean... \nAn example of simple diffusion is that of steroid hormones which diffuse readily through the cell mebrane and reach their target molecules within the cell.\n\nFacilitated diffusion you have for example for the uptake of many hydrophilic/charged nutrients from the blood. The concentration of the nutrient is higher on the outside of the cell, yet it cannot simply diffuse through the membrane; it needs the help of transport proteins.\n\nActive transport means that the cell needs to import something uphill its gradient, using energy. The most profound example is the Na+/K+  ATPase which pumps Na+ out of the cell and K+ into the cell using ATP (both Na+ export and K+ import are uphill processes).\n\nA beautiful combination of passive and active transport is seen in the intenstinal epithelial cells. The concentration of glucose in the gut is lower than inside the cell. So the human body needs to consume energy and actively import glucose. This happens via a symporter that imports Na+ together with glucose. The import of Na+ is downhill so it releases energy which is used for the uptake of glucose. Once the glucose is inside the epithelial cell it will be passively exported to go to to the bloodstream.
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movement of molecules is primarily the only similarity. With active transport molecules move from an area of lesser concentration to an area of greater concentration, this requires energy.  Diffusion is also the movement of molecules but they move from an area of grater concentration to an area of lesser concentration; occurs because molecules have free energy, like the diffusion of o2 &co2 in the lungs
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In both cases you have a semi-permeable membrane separating two solutions.\n\nIn the case of osmosis, solutes (which contribute to the phenomenon) cannot pass through the membrane and therefore the solvent has to pass through the membrane in order to equilibrate the osmotic pressure (or better yet the solvent potential) of the two solutions.\n\nIn the case of dialysis you have some solutes which can pass through the mebrane and diffuse from the solution where their concentration is higher to the one where their concentration is lower. Thus dialysis is used when you want to get rid of certain solutes or exchange them with others, while retaining some of the initial solutes in your system. E.g. if you have a protein sample that has too much salt, you can get rid of the salt (or any other small molecule that you don't want in your sample), without losing your protein, by dialysis; you can change the buffering system with dialysis. Of course there are also the medical aspects of dialysis but these have already been described in detail in the other answer.\n\nIn two words, in the case of osmosis you have net movement of solvent whereas in dialysis you have net movement of some solutes from one solution to the other.
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passive diffusion is wen substances move past the membrane without any use if cell energy.\nfacilitated diffusion are hundreds of protein channels have been found that allow particular substances to cross different membranes. Fast and specifif. Does not require energy