Contact Us. The Galleries:. Photo Gallery. Silicon Zoo. Chip Shots. DNA Gallery. Amino Acids. Religion Collection. Cocktail Collection. Screen Savers. Win Wallpaper. Mac Wallpaper. Movie Gallery. Ribosomes All living cells contain ribosomes, tiny organelles composed of approximately 60 percent ribosomal RNA rRNA and 40 percent protein.
Send us an email. Davidson and The Florida State University. All Rights Reserved. Cell Structure 3. Membrane Structure 4. Membrane Transport 5. Origin of Cells 6. Cell Division 2: Molecular Biology 1. Metabolic Molecules 2.
Water 3. Protein 5. Enzymes 6. Cell Respiration 9. Photosynthesis 3: Genetics 1. Genes 2. Chromosomes 3. Meiosis 4. Inheritance 5. Genetic Modification 4: Ecology 1. The smaller subunits tow and attach the corresponding amino acid to the growing length of protein. They are free to move around anywhere other than the nucleus and other organelles. The detached ribosomes create proteins that are released directly into the cytoplasm for use by the cell. A peculiarity of cytoplasm is that it contains high concentrations of glutathione, a short protein segment containing the amino acid cysteine.
This environment prohibits proteins with sulfur in the form of a disulfide bond from being made by the detached ribosomes. The types of proteins made by the two different ribosome types differ in other ways beyond disulfide bonds. Detached ribosomes figure heavily in cellular metabolism and generate enzymes that release the energy from glucose molecules. Attached ribosomes make proteins targeted for specific purposes outside the cell, such as digestive enzymes used in the gut.
They also produce hormones and certain cell membrane proteins that act as surface receptors.
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