Chapter 23: Digestive System

Front

Explain how the enteric nervous system supports the digestive system. What might occur that could result in the autonomic nervous system having a negative impact on digestion?

Back

The enteric nervous system regulates digestive processes, controlling peristalsis and enzyme secretion. If the autonomic nervous system is negatively impacted, it can lead to issues like reduced motility or secretion, causing digestive disorders.

Front

What layer of the alimentary canal tissue is capable of helping to protect the body against disease, and through what mechanism?

Back

The mucosa layer protects against disease through the secretion of mucus and antibodies, which trap pathogens and prevent their entry.

Front

Offer a theory to explain why segmentation occurs and peristalsis slows in the small intestine.

Back

Segmentation allows for mixing and absorption of nutrients, while slowed peristalsis ensures that food remains in the small intestine longer for optimal nutrient absorption.

Front

What type of reflex is triggered when you smell freshly baked bread, and what is the result?

Back

The reflex triggered is a cephalic reflex, resulting in increased salivation and preparation of the digestive system for food intake.

Front

Discuss how saliva produced by the parotid gland differs in action from saliva produced by the sublingual gland.

Back

Parotid gland saliva is primarily serous and rich in enzymes, aiding in digestion, while sublingual gland saliva is more mucous, providing lubrication.

Front

Which teeth did the player lose when all eight anterior teeth were knocked out, and how does this loss affect food ingestion?

Back

The player lost his incisors, which are crucial for cutting food. This loss can hinder the ability to bite and chew effectively.

Front

What prevents swallowed food from entering the airways?

Back

The epiglottis prevents swallowed food from entering the airways by covering the trachea during swallowing.

Front

Explain the mechanism responsible for gastroesophageal reflux.

Back

Gastroesophageal reflux occurs when the lower esophageal sphincter fails to close properly, allowing stomach acid to flow back into the esophagus.

Front

Describe the three processes involved in the esophageal phase of deglutition.

Back

The three processes are: 1) voluntary phase - pushing the bolus to the back of the mouth, 2) pharyngeal phase - involuntary contraction of pharyngeal muscles, and 3) esophageal phase - peristalsis moving the bolus down the esophagus.

Front

Explain how the stomach is protected from self-digestion and why this is necessary.

Back

The stomach is protected by a thick mucus layer and the secretion of inactive enzymes, preventing damage to its own tissues from acidic gastric juices.