. Parietal cells secrete ________.

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.

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

C) storing the carbohydrate reserve glycogen

- Correct: One of the functions of the liver in human adults is storing the carbohydrate reserve glycogen. Glycogen is a polysaccharide that serves as a storage form of glucose in the body. When blood glucose levels are high, such as after a meal, the liver takes up excess glucose and converts it into glycogen for storage. When blood glucose levels drop, such as between meals or during fasting, the liver breaks down glycogen and releases glucose into the bloodstream to maintain blood sugar levels within a normal range.

A) manufacturing red blood cells

- Incorrect: The primary site of red blood cell production (erythropoiesis) in adults is the bone marrow, not the liver. While the liver is involved in the production of blood proteins and components, such as albumin, clotting factors, and plasma proteins, it is not responsible for manufacturing red blood cells.

B) producing chemical compounds known as auxins

- Incorrect: Auxins are a class of plant hormones involved in various physiological processes, such as cell elongation, apical dominance, and root development. They are not produced by the liver in human adults.

D) synthesizing the hormone insulin

- Incorrect: Insulin is a hormone produced by the pancreas, not the liver. Insulin plays a crucial role in regulating blood sugar levels by facilitating the uptake of glucose into cells for energy production or storage. While the liver responds to insulin by regulating glucose metabolism and storage, it does not synthesize insulin itself.