[Campbell Biology P.112] Which of the following statements is true regarding the Phosphate g... | Practice Question
Which of the following statements is true regarding the Phosphate group -OPO3^2- ?
A: It contributes a negative charge of 1- when positioned inside a chain of phosphates, and 2- when at the end. It also allows molecules to react with water and release energy.
B: It acts as a base, accepting H+ in living organisms, and is characteristic of amino acids.
C: It affects gene expression and the shape of sex hormones when bonded to DNA or proteins.
D: It helps dissolve compounds like sugars due to its polarity and forms carboxylic acids.
Explanation
The Phosphate group contributes a negative charge 1- when inside a chain, 2- when at the end and, when attached, confers on a molecule the ability to react with water, releasing energy. This aligns directly with the description in the table.