WCL Staff Nurse - 2022: What is the biological function of copper?

WCL Staff Nurse - 2022

Applied Nutrition & Dietetics

Easy

Appeared in: WCL Staff Nurse - 2022

Explanation

Copper is an essential trace mineral that serves as a critical component for numerous enzyme systems in the body.
Its primary function is to act as a cofactor for these enzymes, which are collectively known as cuproenzymes.
These enzymes are involved in vital processes such as energy production (cytochrome c oxidase), antioxidant defense (superoxide dismutase), connective tissue formation (lysyl oxidase), and iron metabolism (ceruloplasmin).
Therefore, copper's role as a cofactor is fundamental to many aspects of human physiology.

Option A: The primary mineral involved in initiating muscle contraction is calcium, which binds to troponin. Sodium and potassium are essential for the action potentials that trigger muscle contraction.
Option C: The transmission of nerve impulses along an axon is primarily mediated by the rapid influx of sodium ions and efflux of potassium ions, which create an action potential.
Option D: The synthesis of thyroid hormones (thyroxine and triiodothyronine) is critically dependent on the trace element iodine, which is incorporated into the hormone structure.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Biological role of the trace mineral copper as background academic context rather than a clinical decision trigger.
Nurses should be aware of conditions that can lead to copper deficiency, such as malabsorption syndromes (e.g., celiac disease), prolonged total parenteral nutrition (TPN), or high-dose zinc supplementation, which can interfere with copper absorption.
Clinical manifestations of copper deficiency include microcytic anemia (that doesn't respond to iron), neutropenia (low white blood cell count), osteoporosis, and neurological symptoms.
Conversely, copper toxicity can occur, most notably in Wilson's disease, a genetic disorder leading to copper accumulation in the liver and brain. Nurses may observe for signs like jaundice, abdominal pain, and neurological changes.

How to Approach the Question

First, identify the core subject of the question, which is the 'biological function of copper'.
This is a factual recall question that tests your knowledge of nutrition and biochemistry.
Evaluate each option based on your understanding of mineral metabolism.
Recall that many trace minerals, including copper, zinc, and manganese, primarily function as cofactors for enzymes.
Eliminate the other options by associating them with their correct primary mineral: muscle contraction with calcium, nerve impulses with sodium/potassium, and thyroid hormones with iodine.
Select the option that accurately describes copper's main role as a cofactor for several essential enzymes.

Concept Tested & Keywords

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