1st October 2011
Every once living thing is composed of cells. Cells are small organisms that control everything in living things. When an organism is made of one or more cells it is called a multi cellular organism. The first person to discover cells was Richard Hooke. The cells that he saw were the dead cells of cork. When he first saw them they reminded him of the cells that nearby monks lived in. there are many different parts of the cell but all serve a purpose. These many parts of the cells are called organelles. A cell lacking a membrane bound nucleus is called a prokaryotic cell. In a eukaryotic cell is a cell in which the organelles are bound in membrane. This is the most common type of cell. The gel-like substance that contains all the organelles in a cell is called the cell membrane. The cell membrane protects the cell from its surroundings. It is made mostly of a double layer of lipids. The membrane is sometimes called semi permeable because it allows some things to enter while rejecting others. The organelle that anchors all other organelles in place is called the cytoskeleton. It maintains the cell’s structure and appearance. Mitochondrion is a sort of self replicating generator that comes in many shapes and sizes. It is most common of all organelles. The rough endoplasmic reticulum secretes proteins into the cytoplasm. All over the rough ER are ribosomes that enhance its abilities. The smooth ER stores calcium and releases it when a muscle contracts triggering its movement. The golgi apparatus is the organelle that processes and packages proteins that are synthesized by the cell. Ribosomes are like factory where RNA is used to synthesize proteins. They can be found on the rough ER. Chromatin is the combination of proteins and DNA that make up the contents of the nucleus. The nucleus regulates and controls everything in a cell. It contains most of the genetic information. The nuclear...
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