Which of the following is true in relation to the urea cycle

First two steps of the urea cycle occur in mitochondria and remaining steps take place in the cytosol. Deficiency of any of the urea cycle enzymes would result in hyperammonemia. Urea is formed by NH3, aspartate (not glutamate) and CO2. In urea, nitrogen atoms are derived from NH3 and aspartate, and source of carbon is CO2.