unit cells for crystals

The cell wall is present only in plant cells. It is made up of a complex polysaccharide (carbohydrate) called cellulose. Its function is to give strength and rigidity to the cell. It is non-living...

Structure of Cell - Cells vary in shape and size. They may be oval, spherical, rectangular, polygonal, spindle shaped, star shaped, rod-shaped or totally irregular like the nerve cell. The diversity in cells is in accordance with the role or function it has t..

Peel off the thin epidermis (skin) in the inner layer of an onion. Neatly spread it in the centre of a glass slide on a drop of water...

The modified form of cell theory is called cell principle. It applies almost completely and universally to living organisms. The cell principle is also called cell doctrine. Following are the statements of cell principle. Life exists only in ce..

The history of the discovery of cells dates back to the 17 t h century and is closely associated with the history of the invention of microscopes. An Italian microscopist Marcello Malpighi studied the structure of some plants and proposed the idea that plants are composed of tiny structur..

Spontaneous redox reactions are the metal displacement reactions. Therefore such reactions have been used for producing electricity. This is done by carrying out these reactions in specially designed units called electrochemical cells. An electrochemical cell is a dev..

Around the cell body are short sensory projections called the dendrons. The fine branches of dendrons are called the dendrites. These short fibres receive messages and pass them on to the cell body or the cyton. The messages from the cyton are carried away by the long axon..

The units of nervous system are specialised cells called the neuron..

Introduction - The cells that make up our body are so small that you could fit over 200 of them on the full stop at the end of this sentence Before we plunge into the chapter, here are some interesting facts about cells. Read on... The word cell is derived from the Lat..

Unit Membrane Concept - The molecular structure of cell membrane is still not clearly known. Several models have been proposed from time to time to explain its structure based on its physico-chemical properties. In the year 1935 Danielli and Dawson proposed that the cell..