Which muscles are primarily responsible for the initial breakdown of food in the digestive process?

• A. Rectus abdominis muscles
• B. Diaphragm muscles
• C. Intercostal muscles
• D. Masseter muscles

Answer: (D)

Verified step by step guidance

1. Begin by understanding the role of muscles in the digestive process. The initial breakdown of food involves mastication, which is the process of chewing.
2. Identify the location where mastication occurs. It takes place in the oral cavity, where food is mechanically broken down by the teeth and muscles.
3. Recognize the primary muscles involved in mastication. These are the muscles that facilitate the movement of the jaw to chew food.
4. Focus on the masseter muscles, which are located on the sides of the jaw. They are one of the strongest muscles in the body and are primarily responsible for elevating the mandible (lower jaw) to close the mouth and chew.
5. Understand that while other muscles like the temporalis and pterygoid muscles also assist in mastication, the masseter muscles play a key role in the initial breakdown of food due to their strength and position.