Microvilli (singular: microvillus) are tiny, finger-like projections that protrude from the surface of cells in various tissues and organs of the body. They are much smaller than cilia and range in length from 0.5 to 1 micrometer and are typically several micrometers in length.
The primary function of microvilli is to increase the surface area of cells, which allows for more efficient absorption and secretion of nutrients and fluids. Microvilli are particularly abundant in the small intestine, where they help with nutrient absorption. The brush-like structure created by microvilli on the surface of the intestinal epithelium significantly increases the surface area available for nutrient absorption.
Microvilli are made up of actin filaments, which are anchored to the cell membrane. They also contain various proteins such as transporters, channels, and enzymes that facilitate the movement of molecules across the cell membrane. Microvilli are dynamic structures with a high turnover rate, and can regenerate quickly after being damaged or lost.
Disorders that affect microvilli can result in a variety of health problems. For example, celiac disease is an autoimmune disorder in which the immune system mistakenly attacks the microvilli in the small intestine, leading to malabsorption of nutrients and other health problems. Some viral and bacterial infections can also damage the microvilli in the respiratory and gastrointestinal tracts, leading to respiratory and digestive problems.
Facts about Microvilli
- Microscopic hairlike projections called microvilli can be seen on the surface of cells in many different body parts.
- Micro and villus, both derived from Latin, mean “little” and “hairy,” respectively, which is how the phrase “microvilli” came to be.
- Microvilli range in size from a few micrometers in width to a few millimeters in length.
- Microvilli are specialized projections from the surface of cells that help with fluid and nutrient absorption and secretion.
- Microvilli are found in high numbers in the small intestine, where they facilitate the digestion of food and the absorption of nutrients.
- Microvilli’s brushlike structure on the intestinal epithelium greatly expands the region of the epithelium that can absorb nutrients.
- The kidney also has microvilli, which play a role in the reabsorption of fluids and salts.
- Actin filaments are the building blocks of microvilli, and they are anchored to the cell membrane.
- They also contain proteins that aid in the transit of molecules across the cell membrane, such as transporters, channels, and enzymes.
- Microvilli are active, rapidly renewing structures that can rapidly recover from damage or loss.
- Certain medications and toxins can alter the structure and function of microvilli.
- Viral and bacterial infections can also destroy microvilli, which can contribute to respiratory and intestinal issues.
- Malabsorption of nutrients, diarrhea, and dehydration are just some of the issues that can arise from a disorder affecting the microvilli.
- Celiac disease, inflammatory bowel disease, and cystic fibrosis are only few of the disorders that can harm microvilli.
- Microvilli play a crucial role in the digestion and absorption of food in developing fetuses, babies, and young children.
- It is possible for environmental factors, such as food, to affect microvilli shape and function.
- Microvilli on the surface of cells are a distinguishing feature that can be used to identify them as belonging to specific categories.
- Furthermore, microvilli can facilitate intercellular communication and signaling.
- Microvilli can combine with one another to generate stereocilia, which are longer and thicker than normal microvilli.
- A pair of stereocilia can be found in the inner ear, where they aid in hearing and equilibrium.
- Increases in both the number and size of microvilli on the surface of cancer cells aid in their invasion of surrounding tissues.
- Biofilms are communities of bacteria that grow on surfaces; microvilli may contribute to their production.
- Environmental factors such as pH and osmolarity can influence microvilli’s capacity to take in nutrients and fluids.
- Microvilli play crucial roles in the health and function of numerous cell types, including epithelial cells, nerve cells, and muscle cells.
- The study of microvilli has yielded numerous discoveries about cell biology and the pathophysiological processes underlying a wide range of illnesses and diseases.