Enterocyte

Definition

Enterocytes are the absorptive epithelial cells that line the small intestine and are responsible for the absorption of nutrients from the digested food into the bloodstream. These specialized cells play a crucial role in the functioning of the gastrointestinal tract.

5 Must Know Facts For Your Next Test

1. Enterocytes contain specialized transport proteins that facilitate the absorption of various nutrients, including carbohydrates, amino acids, lipids, and vitamins.
2. The large surface area of the small intestine, due to the presence of villi and microvilli on enterocytes, allows for efficient nutrient absorption.
3. Enterocytes also secrete digestive enzymes, such as lactase and sucrase, to further break down nutrients for absorption.
4. Disruption of the normal function of enterocytes can lead to malabsorption syndromes, such as celiac disease or lactose intolerance.
5. Certain viruses, such as rotavirus and norovirus, can target and infect enterocytes, leading to viral gastroenteritis and diarrhea.

Review Questions

• Explain the role of enterocytes in the absorption of nutrients from the small intestine.
  • Enterocytes are the primary absorptive cells lining the small intestine. They contain specialized transport proteins and a large surface area, due to the presence of microvilli, which allows for the efficient absorption of various nutrients, including carbohydrates, amino acids, lipids, and vitamins. Enterocytes also secrete digestive enzymes to further break down nutrients for absorption. The disruption of normal enterocyte function can lead to malabsorption syndromes, highlighting their crucial role in the digestive process.
• Describe how the structural features of enterocytes, such as microvilli and tight junctions, contribute to their function.
  • The structural features of enterocytes play a critical role in their absorptive function. Microvilli, finger-like projections on the apical surface of enterocytes, create a brush border that significantly increases the surface area for nutrient absorption. Additionally, tight junctions between adjacent enterocytes regulate the movement of substances across the intestinal epithelium, controlling the paracellular transport of nutrients, electrolytes, and water. These specialized features of enterocytes allow for the efficient and selective absorption of essential nutrients from the digested food in the small intestine.
• Analyze the impact of viral infections, such as rotavirus and norovirus, on the function of enterocytes and the resulting gastrointestinal symptoms.
  • Certain viruses, like rotavirus and norovirus, can directly target and infect enterocytes, the absorptive epithelial cells lining the small intestine. This disruption of normal enterocyte function leads to the development of viral gastroenteritis, characterized by symptoms such as diarrhea, vomiting, and abdominal pain. The infection and destruction of enterocytes impairs their ability to absorb nutrients, electrolytes, and water, resulting in the malabsorption and subsequent loss of these essential components through the gastrointestinal tract. Understanding the impact of viral infections on enterocytes is crucial for recognizing the underlying mechanisms behind the clinical manifestations of viral gastroenteritis.

Related terms

Microvilli: Finger-like projections on the apical surface of enterocytes that increase the surface area for nutrient absorption.

Brush Border: The dense array of microvilli on the apical surface of enterocytes, creating a brush-like appearance that enhances nutrient absorption.

Tight Junctions:

Specialized cell-to-cell connections between enterocytes that regulate the movement of substances across the intestinal epithelium.