Answer the question by choosing appropriate responses from the following:
1) Sodium: It is reabsorbed from the proximal convoluted tubule in exchange for potassium.
2) Potassium ions: They are present outside the cell in a 10 times higher concentration than inside.
3) Calcium: It has the least concentration in the sarcoplasmic reticulum.
4) Hydrogen ions: They are secreted in the renal tubules to reabsorb K + ions.
5) Phosphate: It is present in the genetic material (DNA and RNA) and also helps in the formation of the energy currency of the cell (ATP).
6) Ammonium ions: They help in the formation of urea in the DCT.
7) Bicarbonate ion (HCO3-): It plays a crucial role in the reabsorption of H + ions in the kidneys.
Which of the above options correctly matches the ions with their descriptions?
