Differentiate the types of transport processes as to the passage of particles through biomembranes.?
971424
turgid pressure, diffusion, na/pa gradient, active/passive transport.
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electrical signals. "An important characteristic of neurons is that they have excitable membranes which allow them to generate and propagate electrical signals." "Membrane potential (or transmembrane potential or transmembrane potential difference or transmembrane potential gradient), is the electrical potential difference (voltage) across a cell's plasma membrane. In membrane biophysics it is sometimes used interchangeably with cell potential, but is applicable to any lipid bilayer or membrane. Hence every organelle and every membranous compartment (such as a synthetic vesicle) has a transmembrane potential (although the size of this potential may be zero)."
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http://en.wikipedia.org/wiki/Biological_membrane\n\nhttp://simscience.org/membranes/advanced/essay/biological_membranes1.html\n\nhttp://web.mit.edu/esgbio/www/cb/membranes/structure.html\n\nhttp://www.sci.uidaho.edu/bionet/biol115/t2_basics_of_life/lesson03/lesson3_mod1.htm\n\nhttp://www.chemsoc.org/ExemplarChem/entries/2002/Tim_Smith/membrane/index.html\n\nhttp://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=stryer.section.1629\n\nhttp://www.csupomona.edu/~dfhoyt/classes/zoo138/BIOL_MEMB.HTML\n\nhttp://www.studyworld.com/newsite/reportessay/Science/Biological%5CComponents_of_Biological_Membranes-384178.htm\n\nis that enough? :-)
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1) The first membrane that a water molecule encounters and passes through is the 'ROOT HAIR CELL MEMBRANE'\n2) Then it passes through all the membranes of the cortical parenchyma of the root in a lateral or roughly horizontal direction (Actual number depends upon the size of the root.)\n3) After entering the xylem element it will not come across any membrane, as the xylem is a dead tissue, and travel in upward direction towards the leaves till it reaches the xylem of a particular leaf. \n4) From the xylem element of the leaf vascular bundle it will enter the mesophyll and in doing so it will once again pass through a cell membrane of that mesophyll cell.  \nNow it is for you to calculate the exact number. I have given you the data.
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Diffusion is the spontaneous spreading of something such as particles, heat, or momentum. The phenomenon is readily observed when a drop of colored water is added to clear water, or when smoke from a chimney dissipates into the air. In these cases, diffusion is the result of turbulent fluid motion rather than chemical reactions or the application of external force. In cell biology, diffusion is described as a form of "passive transport", by which substances cross membranes. \n\nOsmosis is the diffusion of a solvent through a semipermeable membrane from a region of low solute concentration to a region of high solute concentration. The semipermeable membrane is permeable to the solvent, but not to the solute, resulting in a chemical potential difference across the membrane which drives the diffusion.
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Solute \n\nSolution \n\nSuspension or Mixture\n\nFiltration\n\nSolvent
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Basically by osmosis. The cell absorbs nutrients and oxygen through the cell wall from the blood circulating in the capillaries. The oxygen is absorbed by the body in an exchange in the lungs and nutrients are absorbed through the small and large intestine and they all travel in the blood stream to the cells.
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active transport is usually classified as endocytosis, exocytosis (pinocytosis or phagocytosis) processes that require cell use of ATP energy from cell respiration to allow molecules to move from LOW concentration to HIGH concentration. It often involves the use of membrane proteins and cell pumps of various kinds to allow substanaces to pass either into or out of the cell.\n\nCellular transport is often described as the movement of substances just within the cytosol or the cytoplasm, not across the cell membrane. ie as substances move from the Golgi to the edge of the cell mbn.
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Osmosis is the movement of water across a barrier.  Diffusion is the movement of other molecules, not necessarily across a barrier. Check out - \nhttp://www.madsci.org/posts/archives/feb2000/951455351.Cb.r.html for a more detailed answer on what diffusion is compared to osmosis.
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external barriers, then mucous membrane, then nonspecific, then specific.
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Gee...broad question...depends what ur transporting.\ne.g. for gases u need a semi-permeable membrane, a thin membrane, a gradient, a moist/mucus surface
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It means that the cell will only let some selected subsatnces cross the cell membrane. It can also be called a semi-permeable membrane. Usually it only allows small molecules to pass through.
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Active transport involves the movement of substances across a cellular membrane from an area of low concentration to an area of high concentration WITH the expenditure of cellular energy. Passive tranport is the movement of substances from a high concentration area to a low concentration area WITHOUT the expenditure of cellulary energy. \n\nOsmosis is the flow of water through a semi-permeable membrane from a high solute concentrated area to a low solute concentrated area. Osmosis is an example of passive transport, as the flow of water follows the concentration gradient.
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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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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.
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2. Cell membrane and Plasma membrane.
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Passive Transport does not require chemical energy to allow molecules across the membrane.  \n\nOne method of passive transport is simple diffusion.  Diffusion is the movement of molecules across a membrane from areas of high concentration to low concentration or along the concentration gradient.  These molecules can pass readily directly through the membrane.\n\nAnother method is facilitated diffusion.  This method is dependant on structures called transport proteins.  These proteins are simply pore like structures that span the width of the membrane.  The two types are pores and gated channels.  Pores always remain open, but gated channels can open and close in response to stimuli.  Also, these pores can only transport molecules down the concentration gradient.  Some transport proteins are also substrate specific, meaning that they can only transport a specific type of molecule.