Kidney
Contents
Key Stage 3
A drawing of a kidney.
Meaning
Kidneys are organs in the excretory system that removes urea and excess water from the blood.
About the Kidneys
- The kidneys are linked to the bladder by ureters.
- The kidneys filter the blood to remove some toxic substances.
Key Stage 4
Meaning
Kidneys are organs in the excretory system that removes urea and excess water from the blood.
About the Kidneys
- The kidneys are responsible for osmoregulation as well as the removal of urea from the blood.
- As blood passes through the kidneys water, urea, glucose and salts diffuse from capillaries into the kidney tubules at in a structure called a nephron. Glucose is completely reabsorbed into the blood while water is selectively reabsorbed depending on the water concentration in the blood.
- The selective re-absorption of water is affected by anti-diuretic hormone. When the levels of anti-diuretic hormone are high most of the water is reabsorbed into the blood. When the levels of anti-diuretic hormone are low the water is not re-absorbed and is passed down the ureters to the bladder.
Extra Information
References
AQA
- Kidneys, pages 155-8, GCSE Biology, Hodder, AQA
- Kidneys, pages 186-191, GCSE Biology; Third Edition, Oxford University Press, AQA
- Kidneys, pages 215, 219-221, GCSE Biology, CGP, AQA
- Kidneys, pages 75, 76, GCSE Biology; The Revision Guide, CGP, AQA
- Kidneys; kidney failure, pages 219, 220, GCSE Biology, CGP, AQA
- Kidneys; kidney transplants, pages 220, 221, GCSE Biology, CGP, AQA
Edexcel
- Kidneys, pages 156, 158-159, GCSE Biology, Pearson, Edexcel
- Kidneys, pages 246-248, 250, 251, GCSE Biology, CGP, Edexcel
- Kidneys, pages 84, 85, GCSE Biology; The Revision Guide, CGP, Edexcel