https://i0.wp.com/www.sciencebold.com/wp-content/uploads/2011/11/a2-7.jpg?fit=800%2C400 400 800 admin http://www.sciencebold.com/wp-content/uploads/2016/07/Untitled-300x114.png admin2011-11-28 02:28:002016-07-26 13:05:22Protoplasm
The physical material that constitutes the living system is called protoplasm (Greek Protos = first, Plasma = form). It was first recognized by Hugo Von Mohl in the middle of the 19th century. It is the essence of life. Huxley described it in the 19th century as “the physical basis of life”. The cell possessing protoplasm is considered as living and those lacking it are dead.
It is more or less, a viscous translucent kind of material that is a complex mixture of many substances and very much like the white of an egg. Protoplasm in a healthy state is turgid and saturated with water (75-90%). As the cell grows, numerous vacuoles appear in the protoplasm. It responds to external stimuli i.e. electric shock, sudden variation of temperature, light, etc. it has a slow and continuous motion and movement. It is semipermeable, for it allows only certain substances.
It is a very complex substance consisting of 75% of water and 25% of other materials. Of dry matter nearly 90% are organic and rests are inorganic. The organic matters are protein, fat, carbohydrate and inorganic salts are phosphate, sulphate, chloride and carbonates of magnesium, potassium, calcium and iron, etc. among them, protein is the chief organic matter.