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Cell Parts. A brief introduction to organelles and their functions By Judy Student. Cell Membrane. The cell membrane is the outermost layer of the cell.
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Cell Parts A brief introduction to organelles and their functions By Judy Student
Cell Membrane • The cell membrane is the outermost layer of the cell. • The membrane is made of proteins, protein channels, and a lipid bilayer that allows for transportation of nutrients and other cellular materials into and out of the cell. • The cell membrane also gives the cell its shape and holds the cytoplasm in.
Cytoplasm • The cytoplasm is the inner matrix of the cell. • Almost all organelles in the cell are suspended in the cytoplasm. • The cytoplasm is the beginning point for many cellular processes, such as cellular respiration.
Mitochondria • Have been called the powerhouse of the cell! • The mitochondria consist of two membranes: an inner membrane and an outer membrane. • The folds of the inner membrane are called cristae. • DNA, ribosomes, or small granules may be found in the inner matrix of the mitochondria.
Endoplasmic Reticulum • There are two parts of the endoplasmic reticulum: the smooth ER and the rough ER. • The rough ER is distinguished from the smooth ER because ribosomes are found studding its walls. • The rough and smooth ER are important for synthesis of lipids and proteins. • It also plays a role in glucogenesis, or the production of glucose.
Nucleus • The nucleus is the genetic hub of the cell. • The nucleus is organized into long strands of genetic material, called DNA, which is short for deoxyribonucleic acid. • Inside the nucleus is the nucleolus, which forms repeats of rDNA , the DNA coding for rRNA.
Vacuole • The vacuole is found only in plant cells. • As an adult plant, up to 90% of the plants volume can be made up of cellular vacuoles. • The vacuole holds liquid sugars and proteins that have been broken down into more simple substances. • Through osmotic pressure, water can go through the vacuoles and into the plants to keep them from wilting.
In Conclusion. . . • Cells are a vital part of life on Earth. • There are many individual organelles within the cells that work together to make the cell work as a whole. • Understanding the roles of the organelles and cells in general is key to understanding life in general!
Images obtained from the following web sites: • http://www.freewebs.com/ltaing/plasma%20membrane.gif • www.east-haven.k12.ct.us/.../cytoplasm.png • http://www.kathleensworld.com/mitochondria.jpg • http://cellbio.utmb.edu/cellbio/mitochondria_1.htm#Substructure • www.cartage.org.lb/.../Nucleus/Nucleus.htm • http://www.concord.org/~btinker/xworkbench_web/unitIII_mini/images/vacuole.jpeg • http://www.cellsalive.com/cells/cellpix/cell_model.jpg