In which digestive system organ does nearly all nutrient absorption occur? (A) stomach (B) small intestine (C) large intestine (D) pancreas

Key Concepts

Nutrient Absorption

Nutrient absorption is the process by which the body takes in essential nutrients from digested food. This occurs primarily in the small intestine, where the inner lining is equipped with villi and microvilli that increase surface area, facilitating the efficient uptake of nutrients such as carbohydrates, proteins, fats, vitamins, and minerals into the bloodstream.

Small Intestine Structure

The small intestine is a long, coiled tube that is divided into three sections: the duodenum, jejunum, and ileum. Each section plays a role in digestion and absorption, with the jejunum and ileum being particularly important for absorbing nutrients. The presence of digestive enzymes and bile in the small intestine further aids in breaking down food for absorption.

Digestive System Overview

The digestive system is responsible for breaking down food into smaller components that can be absorbed by the body. It includes organs such as the mouth, esophagus, stomach, small intestine, large intestine, and accessory organs like the pancreas and liver. Understanding the function of each organ helps clarify where and how nutrient absorption occurs, with the small intestine being the primary site.