What is Facebook?

Facebook is a social networking service launched on February 2004 owned and operated by Facebook Inc. Facebook was firstly introduced by Mark Zuckerberg.   As of September 2012 Facebook has over 1 billion active users. From this one billion active users half of them use Facebook from their mobile device. Users must register to Facebook before using the site, nowadays most of them have Facebook account so it is easy to communicate with each other without any cost. Facebook had well grown all over the world. One of the main disadvantage of Facebook is everyone get's addicted with Facebook. A student use to spend more than a hour or two hour in front of Facebook It permits a rule that children less than 13 years of age are not allowed to signup for Facebook. But this age restriction is restricted by the new mode generation children's  Many of the great apps on Facebook makes the users more entertained. Facebook has been a source for introducing business activities. Huge traffic have been transformed from Facebook to other website.

What is internet?

Internet is a computer based worldwide information network. It can be assumed as an example of Wide Area Network. The internet is composed of a large number of smaller interconnected networks. These networks may link tens, hundreds, or thousands of computers, enabling them to share information with each other and to share various resources, such as powerful supercomputers and database of information.  The internet has made it possible for people all over the world to effectively and inexpensively communicate with each other. Unlike traditional broadcasting media, such as radio and television, the internet is a decentralized system. Each connected individual can sell products with a minimum overhead cost. The internet has brought new opportunity for business to offer goods and services online and it has shown dramatic impact on higher education as more universities offer internet based courses.

What is cartilage?

Cartilage is soft and flexible. It is non porous. In case of cartilage blood vessels are absent. In cartilage matrix is made up of proteins and there is no deposition of calcium phosphate. In cartilage bone marrow is absent.

What is bone?

Bone is hard and flexible. It is pores. In case of bone blood vessels are present. In bone matrix is made up of calcium phosphate. Inside the bone there is a brownish particles called bone marrow.

What are complex tissue?

The complex tissue are made up of more than one type of cells, They work together as a single unit. The main functions is conduction. Xylem and Phloem are the complex tissue and are the component parts of the vascular bundle.

What are epithelial tissue?

Epithelial tissue serves as a protective covering. It covers both external surface of the organs including blood vessels. Epithelial tissue rests on a non cellular basement membrane. This membrane separates the epithelium from underlying connective. Blood vessels are absent on the epithelial tissue. The cells of the epithelial tissues fit tightly without inter cellular space. Injuries are likely to heal rapidly as well as cells divide and produce new cells to replace the lost damaged cells. Functions of epithelial tissues are protection, absorption, secretion, sensory perception. Based on the number of layers the epithelial tissue is classified into simple and stratified epithelium.

What is sclerenchyma?

Sclerenchyma are called dead tissue. Considerably thicken with lignin deposition. Inter cellular space are absent. Based on the shape sclerenchyma are of two types, fibres and schelereids. cells of the fibres are elongate whereas cells of schelerids is irregular in shape. Its main functions are: it gives mechanical support, it gives protection from various adverse conditions, It helps in the conduction of water, hardness of the pulp is due to sclerenchyma, it also has economical importance eg: jute, fibre etc.