Question

eous solutions to release charged, inorganic atoms or substances called ions. in biological sys
mportant ions are

e
um, calcium, manganese, and potassium.
um, calcium, potassium, and phosphate.
um, calcium, zinc, and oxygen.
m, phosphate, nitrogen, and potassium.

Explanation:

To solve this, we analyze the options based on the definition of ions (charged inorganic atoms/substances) and biological relevance:

1. Option 1 (e.g., sodium, calcium, manganese, potassium): Manganese is a trace ion but less common as a "most important" ion in general biological systems compared to others.
2. Option 2 (e.g., sodium, calcium, potassium, and phosphate): Sodium, calcium, and potassium are major cations; phosphate is a major anion. All are critical for processes like nerve signaling, muscle contraction, and energy transfer (e.g., ATP).
3. Option 3 (e.g., sodium, calcium, zinc, and oxygen): Oxygen is a neutral molecule (not an ion) in this context, so this is invalid.
4. Option 4 (e.g., sodium, phosphate, nitrogen, and potassium): Nitrogen is often part of organic molecules (e.g., proteins, nucleic acids) and not typically a free ion in the same way as the others.

Answer:

(Assuming the second option is formatted as, e.g., "B. sodium, calcium, potassium, and phosphate" – the correct option is the one with sodium, calcium, potassium, and phosphate, as these are all charged inorganic ions critical in biological systems.)