Each state of the United States selects two senators to represent their states in the United States Senate. In 1913, the 17th Amendment[?] to the United States Constitution provided for the direct popular election of senators; prior to this, senators were selected by state legislatures.
... oxygen.
The light reaction also generates ATP by powering the addition of a phosphate group to ADP, a process called photophosphorylation[?]. ATP is a versatile source of ...