Editing Human body (section)

===Tissues===
[[File:DIagram of the different types of soft tissue in the body CRUK 037.svg|thumb|Diagram of the different types of [[soft tissue]] in the body]]
The body consists of many different types of [[Tissue (biology)|tissue]], defined as cells that act with a specialised function.<ref>{{Cite web |url=https://en.oxforddictionaries.com/definition/tissue |archive-url=https://web.archive.org/web/20161005004435/https://en.oxforddictionaries.com/definition/tissue |url-status=dead |archive-date=5 October 2016 |title=tissue – definition of tissue in English |work=[[Oxford Dictionaries (website)|Oxford Dictionaries]]{{!}} English |access-date=17 September 2016}}</ref> The study of tissues is called [[histology]] and is often done with a [[microscope]]. The body consists of four main types of tissues. These are lining cells ([[Epithelium|epithelia]]), [[connective tissue]], [[Nervous tissue|nerve tissue]] and [[Muscle|muscle tissue]].{{sfn|Gray's Anatomy|2008|p=27}}

====Cells====
Cells that line surfaces exposed to the outside world or gastrointestinal tract ([[Epithelium|epithelia]]) or internal cavities ([[endothelium]]) come in numerous shapes and forms – from [[Epithelium|single layers of flat cells]], to cells with small beating hair-like [[Cilium|cilia]] in the lungs, to column-like cells that line the [[stomach]]. Endothelial cells are cells that line internal cavities including blood vessels and glands. Lining cells regulate what can and cannot pass through them, protect internal structures, and function as sensory surfaces.{{sfn|Gray's Anatomy|2008|p=27}}