Second Chamber implies that is is the upper house, and legislative body implies it is a part of the bicameral legislature, yes. However, in my opinion, the question in the Pol. Sci. paper was not limited to only legislative powers of the US Senate. You have to mention the checks and balances functions the Senate performs, in both papers. You have to mention that if the Senate is dominated by one party, and the President is from the other party, passing any legislation could become difficult. Another example you have to mention in both papers is that the Senate confirms any of the executive's appointments, such as the Chief Justice of the Supreme Court. You may mention any other example which showcases any of the chamber's powers.

The House of Representatives and the Senate have equal legislative powers, hence to say that the Political Science paper required you to focus only on the legislative functions is an erroneous stance, in my opinion. The special feature of the US Senate, which sets it apart not only from the House of Representatives, but also other Upper Houses around the world, is the oversight it enjoys over the executive's actions as well as the ability to impeach him/her. So, in both questions, you have to mention all three of the Senate's powers: legislative, executive, and judicial.