Arrow (down) icon.An arrow icon, usually indicating that the containing element can be opened and closed. 1  Screening for Prostate Cancer Minus iconIcon indicating subtraction, or that the element can be closed. Plus IconIcon indicating addition, or that the element can be opened.
The small intestine is a long, highly convoluted tube in the digestive system that absorbs about 90% of the nutrients from the food we eat. It is given the name âsmall intestineâ because it is only 1 inch in diameter, making it less than half the diameter of the large intestine.
In the digestive system, absorption means the uptake of digested food into the blood.   Diffusion is one way in which food can be absorbed into the blood. If the conc â¦ entration of food is higher in the intestine than it is in the blood, food can diffuse down the concentration gradient into the blood.   If the concentration of food is lower in the digestive system than in the blood then it cannot be absorbed by diffusion.