Which phase of deglutition involves contraction of the longitudinal muscle layer of the muscularis?

Answer Explanation

d. all of the above

- Correct: All of the statements are true regarding the stomach:

a. muscles churn and mix the food with acids and enzymes: The stomach has muscular walls that contract and relax to mechanically churn and mix food with gastric juices, including hydrochloric acid and various enzymes (such as pepsin) that aid in the digestion of proteins.

b. glands make 3 quarts of digestive juices each day: The gastric glands in the lining of the stomach produce gastric juice, which contains hydrochloric acid, enzymes (such as pepsinogen), mucus, and intrinsic factor. These glands collectively secrete about 2 to 3 liters (quarts) of gastric juice per day.

c. food leaves as a thick liquid called chyme: After mixing with gastric juices and undergoing partial digestion in the stomach, food is transformed into a semi-liquid mixture called chyme. Chyme is then gradually released from the stomach into the small intestine for further digestion and absorption.

Therefore, all of the statements accurately describe processes that occur in the stomach.

Answer Explanation

D) diarrhea

- Correct: Diarrhea is a disorder of the digestive system that can cause severe dehydration. Diarrhea is characterized by frequent, loose, or watery bowel movements, often accompanied by abdominal cramps, bloating, and urgency. It occurs when the intestines fail to properly absorb water or when excess fluid is secreted into the intestines. Diarrhea can lead to significant fluid loss and electrolyte imbalance, resulting in dehydration, particularly if not promptly treated by replenishing lost fluids and electrolytes.

A) appendicitis

- Incorrect: Appendicitis is inflammation of the appendix, a small pouch located near the junction of the small and large intestines. While appendicitis can cause symptoms such as abdominal pain, fever, and vomiting, it is not directly associated with dehydration.

B) gallstones

- Incorrect: Gallstones are hardened deposits that form in the gallbladder and can cause symptoms such as abdominal pain, nausea, and jaundice. While gallstones can lead to complications such as obstruction of the bile duct, they are not directly associated with dehydration.

C) constipation

- Incorrect: Constipation refers to infrequent bowel movements or difficulty passing stool, often characterized by hard, dry stools that are difficult to pass. While severe constipation can cause discomfort and complications such as fecal impaction, it is not directly associated with dehydration.

Answer Explanation

b) propulsion

- Correct: Propulsion is the movement of food along the length of the alimentary canal, from the mouth to the anus. This process occurs throughout most of the alimentary canal and includes both swallowing (deglutition) and peristalsis. Swallowing moves food from the mouth to the esophagus, while peristalsis involves rhythmic contractions and relaxations of smooth muscles in the walls of the digestive organs, pushing food forward through the esophagus, stomach, and intestines.

a) Ingestion: Ingestion refers to the intake of food into the mouth, which occurs at the beginning of the alimentary canal.

c) Segmentation: Segmentation involves the mixing and churning of food within certain regions of the digestive tract, particularly the small intestine. It does not occur throughout most of the alimentary canal but rather in specific areas where mechanical digestion and absorption are optimized.

d) Absorption: Absorption is the process by which nutrients and water are taken up from the digestive tract into the bloodstream or lymphatic system. While absorption occurs primarily in the small intestine, it also occurs in other parts of the alimentary canal, particularly in the large intestine, but it is not a continuous process throughout most of the alimentary canal like propulsion.