Only from area of high conc to low conc When it needs to get out of cell

Only from area of high conc to low conc when it needs

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Only from area of high conc to low conc When it needs to get out of cell against the conc gradient it leads to active transport OSMOSIS: Osmosis is a special kind of diffusion It is the diffusion of water across a selectively permeable membrane It is only about movement of water Solvent: Material doing the dissolving Solute : Particles dissolved in water Solution : Collective is the solution Water moves from a high conc. of water to a low conc. until the conc. Is equal on both sides (equilibrium) Right side has higher concentration of water High water concentration → low solute concentration Low water concentration → high solute concentration High water to low water → low solute to high solute concentration Same thing In osmosis, we talk only about water that's why it is like this
Important in maintaining water balance in cells TONICITY: Hypertonic solution: Excess Higher concentration of solute Water leaves the cell If we put cell in hypertonic solution, cell will shrink Hypotonic solution: Under Lower concentration of solute Water is absorbed by the cell If we put cell in hypotonic solution, cell will swell Isotonic solution: Equal concentration of solute No net movement if water No net osmosis OSMOTIC PRESSURE: Pressure that must be exerted on the hypertonic side of a selectively permeable membrane to prevent diffusion of water from the hypotonic solution TURGOR PRESSURE: It helps plants stay upright Plant cells have plasma membrane as well as cell wall, it helps them react in a different way when place in different solution When it is placed in hypotonic solution, cell won't burst, water is going to fill up the large central vacuoles, which will exert turgor pressure on cell wall, which helps in keeping the cell rigid, leading to plants being upright
When a plant cell is placed in a hypertonic solution, plasmolysis occurs, which refers to the separation of cell membrane from the cell wall. This leads to wilting in plants. Plasmolysis
ACTIVE TRANSPORT: It requires energy or ATP Cells use energy to from metabolic activities to pump substances against the concentration gradient from an area of low concentration to a high concentration Active because energy is required to drive substances AGAINST the gradient Two types: Direct active transport We have two different molecules or ions which are pumped against their conc. Gradient Eg, Na+ K+ pump We are transporting 3 Na+ ions out and 2 K+ ions in Sodiums bind to the protein which will change shape and atp adds K to protein which changes shape to open it up outside the cell, hence the 3 molecules are transported outside
Hence, K joins the protein which then moves from outside to inside of cell Direct : both ions are transported against the conc gradient Indirect active transport: Cotransport A transport protein cotransporter 2 solutes One solute DOWN its conc. Gradient

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