What do buffers do, and why are they important in biological systems?

This is related to bio 181 regarding an exparment with pH levels. I am not shure how to relate it to the biological system. in most organisms, the pH is kept relatively constant by buffers. buffers minimize changes in pHWhat do buffers do, and why are they important in biological systems?
Buffers are chemicals that make a solution capable of absorbing large amounts of acid or base without experiencing any change in pH. You can doubtless pull better definitions out of any of the numerous online dictionaries.



Buffers are important to biological systems because they enable the organism to maintain homeostasis (you have to include that word in your answer) with little physiological cost.



By enabling cells or systems to absorb chemical changes without experiencing pH changes buffers make it possible for organisms to survive in variable environments without wasting vast amounts of energy trying to monitor and adapt to every minor change in physical conditions. They similarly allow organism to engage in activity that will cause the addition of large quantities of acids and bases without risking death or wasting resources trying to deal with it. Most notably they allow organisms to tolerate the acid build up associated with respiration as well as allowing the consumption of acid or alkaline foodstuffs.



Tack on a brief description of the carbonate buffer system in the mammalian blood and you檙e good to go.What do buffers do, and why are they important in biological systems?
Buffers are substances that have specific salt levels to regulate osmosis and to maintain a specific pH. A practical example, cells can shrink or explode when there is too much/too little salty liquid on the inside or outside of the cell, a buffer can regulate the cell system. (look up turgid)
If the pH of a system gets out of whack, many chemical reactions that occur in an biological system will behave much differently. So, for example, if some function can only occur in an environment with a pH between 5.5 and 5.8, a buffer will ensure that the pH is kept within that range.
Don't forget to consider the sensitivity of enzymes to pH (the affect of pH on enzyme activity).

This applies to both intra- and extra-cellular proteins too; cytoplasmic pH and plasma pH must be stabilised.
you got great answers from everyone. I'd add from experience that when you are checking the pH, either in blood (biological system) or in the lab (inorganic system, ie test tube), you should be aware of your breathing as a source of error. Hold your breath if possible, the CO2 did throw off my data considerably when I did a similar experiment.