If by officers you mean representatives, and by legislative branch, you mean the federal legislative branch, then there are 435 members of the House of Representatives and 100 Senators. The Vice President is also the President of the Senate, but only votes in the case of a tie. Therefore, your answer could be that there are either 535 or 536 depending on whether you count the VP.
Its current membership is 435.
source: http://www.america.gov/st/usg-english/2008/May/20080624220626eaifas0.5616876.html
435
All of the members of this legislative body were patricians. wrong.....the answer is senate
The Legislative Body of Members
The are 188 members including 47 State Senators and 141 members of the House of Delegates.
The main legislative body in South Korea is called the National Assembly. It is a unicameral body of about 300 members.
255
90
The U.S. Senate
156
Lobbying .
It is a one-Chamber Parliament, consisting of 550 members.
225
The U.S. senate has 50 members. The ancient Roman senate had at least 600 members. But remember the senate of ancient Rome was not a legislative body as the U.S. senate. The Roman senate was basically a consulting body.