A disease that attacks and disables the myenteric plexus would most likely:

• A. reduce hormone secretion from the pancreas
• B. impair peristalsis in the gastrointestinal tract
• C. increase oxygen transport in the blood
• D. cause loss of sensation in the skin

Answer: (B)

Verified step by step guidance

1. Understand the role of the myenteric plexus: The myenteric plexus, also known as Auerbach's plexus, is a network of neurons located in the walls of the gastrointestinal (GI) tract. It primarily controls the motility of the GI tract, including the process of peristalsis, which is the rhythmic contraction and relaxation of muscles to move food through the digestive system.
2. Analyze the options provided: Evaluate each option in relation to the function of the myenteric plexus. For example, hormone secretion from the pancreas is regulated by other mechanisms, such as hormonal and neural signals, not directly by the myenteric plexus.
3. Focus on peristalsis: Since the myenteric plexus is directly responsible for coordinating peristalsis, damage to it would impair this process, leading to difficulties in moving food through the GI tract.
4. Eliminate unrelated options: Increased oxygen transport in the blood and loss of sensation in the skin are unrelated to the function of the myenteric plexus, as these involve the circulatory and nervous systems, respectively, and not the enteric nervous system.
5. Conclude the correct answer: Based on the analysis, the most likely effect of a disease attacking the myenteric plexus would be impaired peristalsis in the gastrointestinal tract.