These are the tiny particles which are either attached to the rough endoplasmic reticulum giving its granular appearance, or freely scattered in the cytoplasm of both plants and animals cells. They are composed of ribonucleic acid and protein (65% RNA & 35% protein).
https://i2.wp.com/www.sciencebold.com/wp-content/uploads/2011/11/Cell-s19.jpg?fit=800%2C579 579 800 admin http://www.sciencebold.com/wp-content/uploads/2016/07/Untitled-300x114.png admin2011-11-28 02:31:002016-07-26 13:30:15Ribosome
They are concerned with the synthesis of protein from amino acid. It is the ribosome, that determine the manner in which the amino-acids become bonded together to form protein. Many of the protein synthesitzed by the ribosome regulate the rate of chemical reaction occurring in the cell. Ribosome can achieve this synthesis in the presence of other two types of RNA. They are transfer RNA (tRNA) & messanger RNA (mRNA).
It was first reported by de Dure in 1955. These are variously shaped bodies usually bounded by single surface membrane. They are mainly found in animal cells. They contain various digestive and hydrolysis enzymes, which when released, destroy unwanted cellular materials. They are often referred to as “suicidal bags”.
When the cells are dead, the lysosomee release their enzymes which rapidly digest the cells. They may also function in the breaking down of cell parts whenever a cell dies.
They are submicroscopic unbranched hollow tubes. They are supposed to take part in conduction and contraction. They promote movement of materials within the cell and form a cytoskeleton, which determines and maintains the shape of the cell.