Large Intestine Movements: Mass Movements Explained

Subject : Biology

Question:

Which type of movement in the large intestine is characterized by strong waves that start midway through the transverse colon and quickly force the contents toward the rectum?

A. Haustral contractions

B. Peristalsis

C. Mass movements

D. Segmentation

Answer:

The correct answer is C. Mass movements.

Expert Verified Solution:

Mass movements are strong, coordinated contractions in the large intestine that move contents rapidly towards the rectum. These movements typically begin in the transverse colon and are characterized by their intensity and efficiency in pushing fecal matter towards the rectum for elimination. Mass movements occur less frequently than other types of intestinal contractions, such as haustral contractions, peristalsis, and segmentation.

• Haustral contractions are localized, slow, and help with the mixing of contents.
• Peristalsis involves rhythmic contractions that move contents along the digestive tract but is not as forceful as mass movements.
• Segmentation involves the churning and mixing of contents to enhance digestion and absorption.

Mass movements are crucial for efficient bowel function and the timely expulsion of waste.