Pepsinogen is produced by __________ and is activated by _________ which is secreted by ________.
chief cells; carbonic anhydrase (CAH); parietal cells
chief cells; hydrochloric acid (HCI); parietal cells
parietal cells; hydrochloric acid (HCI): chief cells
parietal cells; carbonic anhydrase (CAH); chief cells
enteroendocrine cells; carbonic anhydrase (CAH); parietal cells
The Correct Answer is B
A. chief cells; carbonic anhydrase (CAH); parietal cells: Chief cells correctly synthesize the zymogen pepsinogen, but carbonic anhydrase is an enzyme, not a direct activator. CAH facilitates the formation of protons within cells but does not catalyze extracellular protein cleavage. Pepsinogen requires a low pH environment for activation.
B. chief cells; hydrochloric acid (HCl); parietal cells: Gastric chief cells secrete inactive pepsinogen into the stomach lumen. Hydrochloric acid, produced by parietal cells via proton pumps, lowers the luminal pH to approximately 2. This acidic environment triggers the autocatalytic conversion of pepsinogen into the active protease pepsin.
C. parietal cells; hydrochloric acid (HCl): chief cells: This selection incorrectly reverses the cellular origins of the enzyme and the acid. Parietal cells are responsible for secreting hydrochloric acid and intrinsic factor, not the zymogen pepsinogen. Chief cells provide the protein substrate but do not produce the acid required.
D. parietal cells; carbonic anhydrase (CAH); chief cells: Carbonic anhydrase is an intracellular enzyme that provides the hydrogen ions for acid production. It is not the molecule that directly interacts with pepsinogen in the gastric lumen. Furthermore, parietal cells do not produce the pepsinogen zymogen required for this reaction.
E. enteroendocrine cells; carbonic anhydrase (CAH); parietal cells: Enteroendocrine cells, specifically G cells, secrete hormones like gastrin into the bloodstream rather than digestive zymogens. Carbonic anhydrase remains an intracellular catalyst for ion formation. This combination fails to describe the luminal activation of proteases necessary for protein degradation.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
A. Subject 1: Because Subject 1 lacks both A and B surface antigens, the individual is classified as having blood type O. In the ABO system, type O is characterized by the absence of these specific glycoproteins. This phenotype results in the presence of both anti-A and anti-B antibodies in the plasma.
B. Subject 2: The sample demonstrates visible agglutination in the presence of Anti-A antiserum while remaining smooth in Anti-B antiserum. This indicates the presence of A antigens and the absence of B antigens on the erythrocyte membranes. Consequently, the ABO blood group for this individual is Type A.
C. Subject 3: There is a clear lack of agglutination in the Anti-A antiserum, but distinct clumping is present in the Anti-B antiserum. The reaction confirms that the red blood cells possess B antigens but lack A antigens. This specific reactivity pattern identifies the individual as having Type B blood.
D. Subject 4: Agglutination is prominently visible in both the Anti-A and Anti-B antiserum wells for this individual. This positive reaction in both tests proves the simultaneous presence of both A and B surface antigens. Therefore, Subject 4 is classified as having blood type AB.
Correct Answer is True
Explanation
True: This clinical term describes the exudate formed during the inflammatory process, particularly in response to pyogenic bacterial infections. It consists of an accumulation of liquefied necrotic tissue, dead and dying leukocytes, and cellular debris. The presence of neutrophils is the hallmark of this acute inflammatory response.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.