# Describe how urea is produced in the liver and then removed from the body.

> Cambridge International IGCSE Biology (0610) — 13.1 Excretion in humans · Describe · 4 marks

## Mark scheme (4 marks)

1. Excess amino acids cannot be stored, so they are broken down (deaminated) in the liver
2. Deamination removes the nitrogen-containing (amino) group from the amino acid, forming urea
3. Urea is carried in the blood to the kidney, where it is filtered out at the glomerulus
4. Urea leaves the body dissolved in urine, which passes from the kidney along the ureter to the bladder and out through the urethra

## Key terms

- [urea](https://www.gradenine.co.uk/glossary/urea)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-urea-is-produced-in-d3d81d82) · Published by Druglandscape Ltd.