Difference between revisions of "Villi"
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===Adaptations of Villi=== | ===Adaptations of Villi=== | ||
| − | : [[Villi]] have a wall only one cell thick so the [nutrient]]s only have a short distance to [[Diffusion|diffuse]] into the [[blood]]. | + | : [[Villi]] have a wall only one cell thick so the [[nutrient]]s only have a short distance to [[Diffusion|diffuse]] into the [[blood]]. |
: [[Villi]] have [[Capillary|capillaries]] in order to constantly supply enough fresh [[blood]] with few [[nutrients]] keeping a high [[Concentration Gradient|concentration gradient]] between the food and the [[blood]]. | : [[Villi]] have [[Capillary|capillaries]] in order to constantly supply enough fresh [[blood]] with few [[nutrients]] keeping a high [[Concentration Gradient|concentration gradient]] between the food and the [[blood]]. | ||
: [[Villi]] have a large [[Surface Area|surface area]] to allow quicker [[diffusion]]. | : [[Villi]] have a large [[Surface Area|surface area]] to allow quicker [[diffusion]]. | ||
Latest revision as of 15:16, 21 February 2020
Contents
Key Stage 3
Meaning
Villi are small folds in the wall of the small intestine that increase its surface area.
Adaptations of Villi
- Villi have a wall only one cell thick so the nutrients only have a short distance to diffuse into the blood.
- Villi have capillaries inside them for a good blood supply to allow for quick diffusion into the blood.
- Villi have a large surface area to allow quicker diffusion.
- The cells in the walls of the villi have microvilli to provide an even bigger surface area for quicker diffusion.
About Villi
- Villi cover inside of the small intestine.
- Villi increase the surface area of the small intestine.
 |
Key Stage 4
Meaning
Villi are small folds in the wall of the small intestine that increase its surface area.
Adaptations of Villi
- Villi have a wall only one cell thick so the nutrients only have a short distance to diffuse into the blood.
- Villi have capillaries in order to constantly supply enough fresh blood with few nutrients keeping a high concentration gradient between the food and the blood.
- Villi have a large surface area to allow quicker diffusion.
- The cells in the walls of the villi have microvilli to provide an even bigger surface area for quicker diffusion.
About Villi
- Villi cover inside of the small intestine.
- Villi increase the surface area of the small intestine.
|
References
AQA
- Villi, page 21, GCSE Combined Science; The Revision Guide, CGP, AQA
- Villi, page 24, GCSE Biology; The Revision Guide, CGP, AQA
- Villi, page 45, GCSE Combined Science Trilogy 1, Hodder, AQA
- Villi, page 59, GCSE Combined Science Trilogy; Biology, CGP, AQA
- Villi, page 65, GCSE Biology, CGP, AQA
- Villi, pages 15, 23, 39, GCSE Biology; Third Edition, Oxford University Press, AQA