The First Step of the Urea Cycle Involves Which of the Following

question 55

Multiple Choice

The first step of the urea cycle involves which of the following substances?

• A)urea
• B)citrulline
• C)NAD⁺
• D)NH₄⁺
• E)P_i

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Definitions:

Upper Leg Muscle

Refers to the muscles located in the thigh region, such as the quadriceps and hamstrings.

Gemellus

A term referring to one of a pair of small muscles located in the buttocks, involved in the rotation of the thigh.

Hip Muscle

The hip muscle is part of a group of muscles around the hip joint that supports movement and stability of the hip, including flexors, extensors, abductors, and adductors.

Piriformis

A muscle in the gluteal region of the lower limb, which can sometimes be involved in sciatic nerve compression.