I band

The I band is a term used to refer to an area within a sarcomere.

A sarcomere is the repeating functional unit of "striped" or "striated" muscle.

"Striated muscle" is also known as "skeletal muscle", "voluntary muscle", and "cardiac muscle". Its striated (stripey) visual appearance is due to alternating (dark) A bands and (light) I bands.

The relative sizes of the H Zone, the A band, and the I band of sarcomeres are determind by, and provide information about, the state of contraction or relaxation of the muscle tissue of which the sacromere is a part.

This is illustrated below:

Above: Diagram of the unit within a muscle cell that is known as a sarcomere

The I band is the region between adjacent A bands, in which there are only thin filaments, and no thick filaments. Each I band extends across two adjcent sarcomeres.


This section consists of short summaries about the structures that form the muscles of the body. This list is not exhaustive but is intended to be appropriate for students of A-Level Human Biology, ITEC courses in massage and related subjects, and other courses in health sciences. For more general information about muscles see the pages about:

In the News:

Garlic and Artichoke adopted through ABC's Adopt-an-Herb Program - 14 Jun '19

Cranberry Harvest underway in USA - 5 Oct '18

Total retail sales of herbal supplements in the USA exceeded $8 Billion in 2017 - 13 Sep '18

It's a bumper blueberry season - 13 Jul '18

Positive effects of exercise on blood cell populations - 20 Jun '18

Benefits of dementia friendly swimming opportunities - 30 May '18

Essential oils used in ambulances - 28 May '18

Psychological benefits of different types of natural environments - 2 Nov '17

The word 'angel' is a collective name for all celestial beings. There are many categories of angels.

Although care has been taken when compiling this page, the information contained might not be completely up to date. Accuracy cannot be guaranteed. This material is copyright. See terms of use.

IvyRose Holistic 2003-2019.