Intermediate filaments range in diameter from 8

Intermediate filaments range in diameter from 8 - water. It...

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Intermediate filaments  range in diameter from 8–12 nanometers, larger than microfilaments  but smaller than microtubules. Intermediate filaments are a diverse class of cytoskeletal units, built from a family of proteins  called keratins. Intermediate filaments are specialized for bearing tension. Intermediate filaments are more permanent fixtures of the cytoskeleton than are the other two  classes. They reinforce cell shape and fix organelle location. Concept 7.7 Extracellular components and connections between cells help coordinate cellular activities Plant cells are encased by cell walls. The  cell wall,  found in prokaryotes, fungi, and some protists, has multiple functions. In plants, the cell wall protects the cell, maintains its shape, and prevents excessive uptake of 
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Unformatted text preview: water. It also supports the plant against the force of gravity. The thickness and chemical composition of cell walls differs from species to species and among cell types within a plant. The basic design consists of microfibrils of cellulose embedded in a matrix of proteins and other polysaccharides. This is the basic design of steel-reinforced concrete or fiberglass. A mature cell wall consists of a primary cell wall, a middle lamella with sticky polysaccharides that holds cells together, and layers of secondary cell wall. Plant cell walls are perforated by channels between adjacent cells called plasmodesmata....
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This note was uploaded on 01/04/2012 for the course BSC BSC1005 taught by Professor Orlando,rebecca during the Fall '10 term at Broward College.

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