Street Studies

The cell has a different internal environment from that of external environment. The difference is maintained throughout the life of cell by the thin membrane, known as cell membrane or plasma membrane. It covers the protoplasm. It is also known as   Plasma Membrane or Plasmalemma.    In animal, this is outer most layer of the cell while in plants it is present beneath the cell wall. read also :  Begining of The Life - The Cell : A Discovery  Structure of Cell Membrane Or Plasma Membrane Cell Membrane Or Plasma Membrane : Structure             i.          It is normally composed of Lipid and protein.          ii.           The composition is : protein – 60 to 80 % , Lipid – 20 to 40 % , cellulose – few , Enzymes – few , water – about 20% of whole weight.          iii.       ...

Plants cell wall thickening provides strengthening to the tissues, structural sup port, enabling upright growth, enhancing resistance to environment. it allows plants to withstand gravity, maintain their shape and protect themselves from damage caused by various factors such as pathogen, insects, extreme temperature etc. read also :  Most Route Changing River in India - Kosi or Dormant Kosi River Thickening   of Cell Wall Thickening of the cell is oftenly done after the cell development. “The process of deposition of substances on the cell wall after cell development, is called as thickening of cell wall. This process is occur only in those cells whose function is transportation and to provide mechanical support. Thus the thickening of cell wall is found in vessels and tracheids cells. Thickening of Cell Wall Various types of substances are deposed off on the cell wall , by which it is classified into following category – read more :   Bt Toxin    ,  ...

On the presence of Cell Wall , the plant cell and an animal cell are differentiate into different sections. We already know that cell wall is absent in animal cells. Different groups such as bacteria, fungi, algae & plant cells possess cell wall but their composition is different. We take a look on these structures – read more :  Earthquakes : Causes, Types and Prevention A.    Cell Wall of a Bacteria We know that bacteria is a prokaryotic cell. The structure of a Bacterial cell wall is complicated in comparison to their structure. It is about 100 A 0  – 250 A 0  thik , rigid & complex in structure. The cell wall is made of polysaccharide, lipid and protein. Beneth the cell wall, there is a cell membrane present which is made of protein and lipid. On the basis of structure & the characteristic of color regent reactions, it is classified into Gram positive and Gram negative bacteria. It has peptidoglycan ( made of two elements – peptide & Glycan )...

The cell theory is mainly proposed by  Schleiden and Schwann, 1839 . According to cell theory all living organisms ( bacteria, plant and animal ) are composed of cell. The cell is the basic structural & functional unit of life. The activities of all living organisms are the result of the actions of their cells. The cell theory is important to understand the development of organisms and living beings. It is also important that any small changes affect the activity of living being. read also :  Freckles : Causes and Home Remedies Cell Wall : Structure Attribution Of Scientist In The Development Of Cell Theory / Brief History Of Cell Theory Robert Hooke, 1665 :  The discussion about cell theory has been started after the discovery of cell by Robert Hooke. Lamarck, 1809 :  Life is not possible for a living being whose organs are not made up of cellular tissues. M. J. Schleiden ( Botanist ) and Theodor Schwann ( Zoologist ) , 1839 :  All plants and animals body a...