Final answer:
Protein should be restricted in cats with uremia to manage the production of nitrogenous waste, which can exacerbate the condition due to compromised kidney function.
Step-by-step explanation:
For a cat with uremia, the nutrient that should be restricted in quantity (not quality) is protein. Uremia is a condition characterized by elevated levels of waste products in the blood, which can occur due to kidney failure. Restricting protein intake is essential in this condition because protein catabolism leads to the production of nitrogenous wastes, which the damaged kidneys cannot efficiently remove from the body. High protein diets can, therefore, exacerbate the symptoms of uremia. Although protein is essential for bodily functions, including being the building blocks of nucleic acids, cells, and tissues, in the case of uremia, it's crucial to manage protein consumption carefully.