Ribosomes,+Vacuoles,+and+Lysosomes

Ribosomes, __//**Vacuoles**//__ and Lysosomes

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Ribosomes are complex particles of RNA and protein in cells. They are about 65% RNA and 35% ribosomal proteins. Ribosomes, through a process called //translation,// turn genetic code from nucleic acid into proteins. This process turns amino acids into peptide chains. =====

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Only about 20nm in diameter, Ribosomes are some of the smallest organells in cells. They tend to be bound to the endoplasmic reticulum (making it "rough" endoplasmic reticulum, as opposed to "soft"). =====


 *  Lysosomes are organelles in either eurkaryotic or prokaryotic cells whos name is derived from the Greek word //lysis// meaning destruction and //soma// which means body.


 *  The Lysosome is a small spherical organelle in a cell ranging from 0.1-1.2 um.


 * ===== The lysosomes primary function is to digest excess or worn-out organelles, food particles and engulfed viruses or bacteria.   =====


 *  The membrane surrounding the Lysosome allows the digestive enzymes within it to work at the optimal pH level of 4.5. Lysosomes fuse with the vacuoles of cells and dispense their digestive enzymes into the vacuole, digesting its contents.


 * ===== The interior of the Lysosomes at 4.8 on the pH scale differ from the cytosol (or the liquid part of the cytoplasm) which has a pH rating of 7.2.   =====


 *  The single membrane of the Lysosome compensates for this by pumping in protons from the cytosol to maintain an optimal pH amount in the Lysosome.

 [| http://www.daviddarling.info/encyclopedia/L/lysosome.html] .
 *  This membrane also keeps the degradative enzymes from leaking out of the Lysosome and damaging the cell

**//__Vacuoles: __//**
Vacuoles are sacs in cells that play a role in intracellular digestion and the release of waste products. Vacuole's are generally small in animal cells and very large in plant cells. They play a role in the turgor pressure of plant cells. when the plant is well watered, water collects in vacuoles. This produces rigidity in the plant cells. The vacuole is that large sac at the center of this plant cell labeled "vacuole" this picture is from http://micro.magnet.fsu.edu/cells/plants/plantmodel.html