Dictionary > Microvillus

Microvillus

Definition
noun, plural: microvilli
Any of the minute hairlike structures projecting from the exposed surface of the cell in order to increase the surface area for absorption, secretion, cellular adhesion, or mechanotransduction
Supplement
Microvillus (pl. microvilli) refers to any of the many microscopic hairlike projections on the surface of certain cells. It is an extension of cytoplasm lined with a plasma membrane; however, there are no organelles but microfilament. The microfilament at the core is made of actin filaments that are bound to each other by fimbrin and villin proteins.
Microvilli can be found on the exposed surface of the epithelial cells of the small intestine and of the proximal convoluted tubule of the kidney.
Microvilli should not be confused with the intestinal villi, which are fingerlike projections at the epithelial lining of the intestinal wall. These villi greatly increase the surface area for absorption. They are covered with a brush border. The brush border is made up of densely packed microvilli. Thus, apart from the villi, the microvilli further increase absorptive surface area of the small intestine.
Word origin: mīkrós (small) + villus (hair)
See also:


You will also like...

"Opabinia regalis"
The Evolutionary Development of Multicellular Organisms

Multicellular organisms evolved. The first ones were likely in the form of sponges. Multicellularity led to the evolutio..

Hominid
The Hominids

The hominid family diversified from the apes around 6 to 8 million years ago. Since then, the evolutionary path has prov..

Biological Cell schematic diagram
Biological Cell Introduction

It only takes one biological cell to create an organism. A single cell is able to keep itself functional through its 'mi..

Still freshwater and plants
Still Freshwater & Plants

Plants in lentic habitats have features not found in terrestrial plants. They acquired these features as they adapt to t..

complete-dominance
Dominance

This tutorial presents Gregor Mendel's law of dominance. Learn more about this form of inheritance and how it can be pre..

Types and Causes of Brain Damage
Types and Causes of Brain Damage

This tutorial describes the different types and causes of brain damage. Find out how genetics, physical injury, lack of ..

Related Articles...

No related articles found

See all Related Topics