Microtubules are a component of the cytoskeleton. These rope-like polymers of tubulin can grow as long as 25 micrometers and are highly dynamic. The outer diameter of microtubule is about 25 nm. Microtubules are important for maintaining cell structure, providing platforms for intracellular transport, forming the spindle during mitosis, as well as other cellular processes. There are many proteins that bind to the microtubule, including motor proteins such as kinesin and dynein, severing proteins like katanin, and other proteins important for regulating microtubule dynamics.

Microtubules are long, hollow cylinders made up of polymerised α- and β-tubulin dimers.

Tubulin dimers polymerize end to end in protofilaments which are the building block for the microtubule structure. 13 protofilaments associate laterally to form a single microtubule and this structure can then extend by addition of more protofilaments to generate the long, hollow, cylindrical structure of a microtubule. Microtubules can extend in length indefinitely.

Professor Timothy John "Tim" Mitchison, PhD, FRS is a British systems biologist. He is Hasib Sabbagh Professor of Systems Biology at Harvard University in the United States.

Mitchison comes from a family of distinguished biologists; he is the son of Avrion Mitchison, his uncles are Denis Mitchison and Murdoch Mitchison, his great uncle was J.B.S. Haldane and his great-grandfather John Scott Haldane. His grandparents were the politician Dick Mitchison and his wife, the writer Naomi (née Haldane). His younger sister Hannah is also a biologist.

Mitchison was educated at the Haberdashers' Aske's Boys' School and completed his undergraduate degree at Merton College, Oxford. Afterward he moved to the University of California, San Francisco in the United States in 1979, where he worked for the Ph.D. under the supervision of Marc Kirschner. At this time he discovered the Dynamic Instability of Microtubules. Later he worked at the National Institute for Medical Research in London. In the late 1980s he returned to San Francisco to become an assistant professor at UCSF. In the late 1990s he moved to Harvard to become co-director of the Institute for Chemistry and Cell Biology at Harvard Medical School. Recently he became deputy chair of the newly formed Department of Systems Biology. He was elected Fellow of the Royal Society in 1997.

Anthony Hyman (1946–1999) was a noted British academic, writer and Islamicist. He died in 1999 and is buried in Brompton Cemetery, London.[1]^{[dead link]}