The physician orders a patient with a duodenal ulcer to take a UREA breath test. Which lab value will the test measure to determine if h. pylori is present?

Correct Answer: D

Rationale: The correct answer is D: Carbon dioxide. The UREA breath test measures the presence of H. pylori in the stomach by detecting the breakdown of urea into carbon dioxide and ammonia by the bacteria. H. pylori produces the enzyme urease, which hydrolyzes urea into ammonia and carbon dioxide. Therefore, an increase in carbon dioxide levels indicates the presence of H. pylori. Choice A (Ammonia) is incorrect because the test does not specifically measure ammonia levels. Choice B (Urea) is also incorrect because the test measures the breakdown of urea, not the urea itself. Choice C (Hydrochloric acid) is incorrect as the test does not directly measure this acid.

Correct Answer: D

Rationale: The correct answer is D because the term mucosa (mucous membrane) refers to the moist surface lining of any hollow organ that communicates with the outside world. This includes organs like the respiratory tract, gastrointestinal tract, and genitourinary tract. The mucosa serves various functions such as protection, absorption, and secretion. Explanation for why the other choices are incorrect: A: A nonkeratinized stratified squamous epithelium describes a specific type of epithelium found in certain areas of the body, but it does not encompass the full definition of mucosa. B: While mucosa may contain mucus-secreting goblet cells, this is not the defining characteristic of mucosa. C: Mucous glands may secrete their product onto the mucosa, but this definition is too specific and does not encompass the full scope of mucosa.

Correct Answer: C

Rationale: The correct answer is C: larger blood vessels. The submucosa is a layer of connective tissue deep to the mucosa, which contains larger blood vessels that supply nutrients to the mucosa and surrounding tissues. This is essential for the maintenance of tissue health and function. The other choices are incorrect because: A: The presence of white blood cells does not differentiate the submucosa from the lamina propria. B: Both the submucosa and lamina propria contain lymphatic tissue, so the amount of lymphatic tissue does not differentiate them. D: Collagen fibers are present in both the submucosa and lamina propria, so the thickness of collagen fibers is not a distinguishing factor.

Correct Answer: B

Rationale: The correct answer is B: a serous membrane, or serosa. The mesentery and lining of the peritoneal cavity are composed of a serous membrane, which is a type of epithelial membrane that secretes a fluid to reduce friction between organs. The outermost layer of the digestive tract is also made up of a serous membrane, known as the serosa. This similarity in composition helps in the smooth movement of organs within the abdominal cavity. Choices A, C, and D are incorrect because the mesentery and peritoneal cavity do not consist of a mucous membrane (mucosa), submucous membrane (submucosa), or endothelial membrane (endothelium).

Correct Answer: A

Rationale: The correct answer is A: keratinized epithelial tissue. Filiform papillae are composed of keratinized epithelial cells that form the whitish tips on the surface of the tongue. These cells are designed to provide a rough surface to help with food manipulation. Collagen (B) is a structural protein found in connective tissue, not in filiform papillae. Mucous (C) is a secretion produced by mucous glands and is not a component of filiform papillae. Taste buds (D) are specialized structures responsible for detecting taste, located in fungiform and circumvallate papillae, not in filiform papillae.