Absorption in the Small Intestine
The small intestine is adapted for absorption with a long length and millions of villi that give a very large surface area.
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The small intestine is adapted for absorption with a long length and millions of villi that give a very large surface area.
- Villi have thin walls and a good blood supply
- Absorbed nutrients enter the blood
- Water is absorbed in the large intestine
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Three questions. Score 2 or more to complete the topic.
What is Absorption in the Small Intestine?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Absorption in the Small Intestine. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain Absorption in the Small Intestine in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Absorption in the Small Intestine helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Absorption in the Small Intestine in detail
The small intestine is adapted for absorbing digested food. Its inner wall is covered with millions of tiny finger-like projections called villi, which greatly increase surface area. Each villus has a thin wall, one cell thick, a rich blood supply to carry away absorbed nutrients and a lacteal for fatty acids and glycerol.
Glucose and amino acids are absorbed by diffusion and active transport into the blood and carried to the liver. The large surface area, short diffusion distance and constant blood flow maintain a steep concentration gradient, making absorption efficient.
How the interactive helps you understand Absorption in the Small Intestine
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Real-life uses and examples
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Common mistakes to avoid
- Listing the steps of a process without saying how one step causes the next.
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Frequently asked questions about Absorption in the Small Intestine
What is Absorption in the Small Intestine?
The small intestine is adapted for absorption with a long length and millions of villi that give a very large surface area.
What are the most important points about Absorption in the Small Intestine?
The main points are: Villi have thin walls and a good blood supply; Absorbed nutrients enter the blood; Water is absorbed in the large intestine.
Why is Absorption in the Small Intestine useful?
Understanding Absorption in the Small Intestine helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Absorption in the Small Intestine?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Absorption in the Small Intestine?
Related topics in Biology include Leaf Structure, Tropisms, Respiration.