Which of the following is the major cation of the extracellular fluids of vertebrates?Multiple choice question.CalciumMagnesiumPotassiumSodium

Breakdown the Problem

To determine the major cation of extracellular fluids in vertebrates, we need to identify the cations listed:

1. Calcium
2. Magnesium
3. Potassium
4. Sodium

Relevant Concepts

Extracellular fluid (ECF) primarily consists of the liquid portion of blood (plasma) and interstitial fluid. The major cations commonly found in ECF are as follows:

• Sodium (Na⁺) is the dominant cation in ECF.
• Potassium (K⁺) is primarily found in intracellular fluid.
• Calcium (Ca²⁺) and Magnesium (Mg²⁺) are present in smaller amounts relative to sodium.

Analysis and Detail

1. Sodium (Na⁺) plays a crucial role in maintaining fluid balance, as well as being essential for membrane potential and signal transmission in cells.
2. Calcium (Ca²⁺) is important for muscle contraction and neurotransmitter release but exists in lower concentrations in ECF compared to sodium.
3. Magnesium (Mg²⁺) is essential for numerous biochemical reactions but is not a major cation in ECF.
4. Potassium (K⁺) predominantly resides within cells, making it less significant as an ECF component.

Verify and Summarize

Sodium is well-known as the primary cation of extracellular fluid. It contributes significantly to the osmotic balance and is involved in electrical signaling.

Final Answer

The major cation of the extracellular fluids of vertebrates is Sodium (Na⁺).