Question

What are the irregular muscular ridges on the inner surface of the heart's ventricles called?

• A. Trabeculae septomarginalis
• B. Papillary muscles
• C. Columnae carneae
• D. Chordae tendineae

Hint:

Columnae carneae are muscular ridges in the ventricles that help strengthen contraction and maintain efficient blood flow during ventricular pumping.

Answer 1

The Correct Option is C

Topic - Biology: Body Fluids and Circulation
Step 1: Understanding the Question:
The question asks for the anatomical name of the muscular ridges found inside the pumping chambers (ventricles) of the heart.
Step 2: Detailed Explanation:
The inner wall of the ventricles is not smooth but contains several muscular structures:
1. Columnae carneae (or Trabeculae carneae): These are the irregular muscular ridges and columns that project from the inner surface of the ventricles. They help prevent suction that would occur with a smooth surface.

2. Papillary muscles: These are specialized cone-shaped muscles that are a part of the columnae carneae. They attach to the chordae tendineae.

3. Chordae tendineae: These are ``heart strings'' or fibrous cords, not muscular ridges. They connect papillary muscles to the valve flaps.

4. Trabeculae septomarginalis: Also known as the moderator band, it is a specific muscular band found only in the right ventricle.
Step 3: Final Answer:
The irregular muscular ridges are called Columnae carneae.