Anatomy of Pharynx and Esophagus Quiz

Cardiac Sphincter

• The cardiac sphincter, also known as the lower esophageal sphincter, is a muscular valve that controls the passage of food from the esophagus into the stomach.

Esophageal Layers

• The muscularis externa layer of the esophagus facilitates peristalsis, the wave-like contractions that push food down the digestive tract.
• The mucosa layer of the pharynx and esophagus is lined with stratified squamous epithelium, which is a type of tissue that provides protection against abrasion from food.
• The submucosa layer of the esophagus contains blood vessels, lymphatic vessels, nerves, and glands.
• The esophageal glands in the esophagus secrete mucus that lubricates the food bolus and helps it move through the esophagus.

Stomach

• The valve that connects the esophagus to the stomach is called the cardiac sphincter.
• The duodenum, jejunum, and ileum are the three regions of the small intestine. The stomach does not have a region called a "jejunum".
• The rugae in the stomach lining allow for the expansion of the stomach when it fills with food.
• The serosa layer is the outermost layer of the digestive system.

Digestive System

• The esophagus operates in a way that allows food to pass through it through peristalsis, a rhythmic contraction of the muscles in the walls of the esophagus.
• The stomach is responsible for the mechanical and chemical digestion of proteins.
• The jejunum is the part of the small intestine responsible for most of the digestion and absorption of nutrients.
• The gallbladder stores and concentrates bile produced by the liver. Bile helps in the digestion of fats.
• The pancreas is responsible for neutralizing acidic chyme from the stomach.
• The ileum absorbs nutrients, specifically vitamin B12 and bile salts.
• The villi and microvilli in the small intestine increase the surface area available for nutrient absorption.
• The hepatic portal circulation transports blood from the digestive tract to the liver, where it is filtered and processed.
• The large intestine is approximately 5 feet long.
• The primary function of the large intestine is to absorb water and electrolytes, and to form and store feces.
• The filling of the stomach triggers the reflexive action of reverse peristalsis in the stomach.
• The duodenum mixes partially digested food with pancreatic juices and bile.

Other Key Functions

• The cardiac sphincter prevents the backflow of stomach contents into the esophagus.
• Villi in the small intestine increase the surface area for nutrient absorption.
• The microvilli in the small intestine provide a huge surface area for nutrient absorption.
• Digestion begins with both mechanical and chemical breakdown of food in the mouth.
• Peristalsis, a wave of muscular contractions, transports food from the pharynx to the stomach.
• The pharynx is a common passage for both air and food.
• The digestive system is a long, continuous tube that includes the mouth, pharynx, esophagus, stomach, small intestine, and large intestine.
• The primary function of the stomach is to churn and mix food with gastric juices, initiating the breakdown of proteins.
• Peristalsis, the wave-like contractions of the stomach muscles, is the process of churning and mixing food with gastric juices.
• The cardiac sphincter prevents the backflow of food from the stomach into the esophagus.
• The four main layers of the digestive system are the mucosa, submucosa, muscularis externa, and serosa.
• The submucosa layer of the digestive system contains blood vessels and lymphatic vessels.
• The muscularis externa layer in the digestive system is responsible for peristalsis, the wave-like contractions that propel food through the digestive tract.
• The pyloric sphincter regulates the passage of food from the stomach into the small intestine.
• The mucosa layer of the digestive system contains specialized cells that secrete digestive enzymes and mucus.
• The serosa layer in the digestive system provides a protective outer covering.
• The tongue plays a crucial role in mechanical digestion by manipulating food within the mouth and aiding in swallowing.

This quiz covers the structure and functions of the pharynx and esophagus. Topics include the divisions of the pharynx, the lining of the oropharynx and laryngopharynx, and the muscular tube of the esophagus for bolus transport.