Site of urea cycle – Biochemistry MCQ

Site of urea cycle is?

A. Liver
B. Kidney
C. GIT
D. Lungs

Correct answer : A. Liver

Site of urea cycle

• Urea cycle (also known as ornithine cycle / Krebs Henseleit cycle) takes place in the liver
• It is responsible for the conversion of toxic ammonia (produced by amino acid catabolism) to urea for excretion
• 5 enzymes are involved in the urea cycle are:
  1. Carbamoyl phosphate synthetase I
  2. Ornithine transcarbamylase
  3. Argininosuccinate synthase
  4. Argininosuccinate lyase (also known as argininosuccinase)
  5. Arginase
• The first 2 enzymes are located in the mitochondria, whereas the other 3 are located in the cytoplasm
• The rate limiting enzyme is Carbamoyl phosphate synthetase I