Complete the stem: rectus femor___

Complete the stem: rectus femor___

• A. Femor
• B. Femoris
• C. Femorus
• D. Femorata

Answer: (B)

The main idea is that many anatomical muscle names use a descriptor plus a genitive noun to show relationship. Here, rectus means straight, and the second word should be the genitive form of the bone name to indicate the muscle associated with that bone. Completing with -is gives rectus femoris, which is the standard name for the muscle known as the straight muscle of the femur. In Latin, femoris is the genitive singular of femur, so the phrase correctly reads as “the straight muscle of the femur.” The other endings don’t fit Latin grammar or established naming conventions for muscles, so they aren’t correct forms for this name.

The main idea is that many anatomical muscle names use a descriptor plus a genitive noun to show relationship. Here, rectus means straight, and the second word should be the genitive form of the bone name to indicate the muscle associated with that bone.

Completing with -is gives rectus femoris, which is the standard name for the muscle known as the straight muscle of the femur. In Latin, femoris is the genitive singular of femur, so the phrase correctly reads as “the straight muscle of the femur.”

The other endings don’t fit Latin grammar or established naming conventions for muscles, so they aren’t correct forms for this name.