For example, a 5 panel drug test checks for 5 drugs, while a 10 panel drug screen checks for 10 drugs. A standard 5 panel drug urine test is the drug test most frequently used by government agencies and private employers.
While a member of the senate is called a senator, a representative is simply called a congressman or a congresswoman. However, collectively, both senators and representatives are also referred to as congressmen. The word Senate comes from the Latin word senate meaning old man.
Congress refers to both houses of the legislative branch of government, the House of Representatives and the Senate. Representative is a member of the House of Representatives... the lower house of Congress. Senator is a member of the Senate, the higher house of Congress.