The baroreceptors in the carotid sinus and aortic arch are sensitive to which of the following?
a decrease in oxygen levels
changes in arterial pressure
an increase in oxygen levels
a decrease in carbon dioxide
The Correct Answer is B
A. A decrease in oxygen levels: While low oxygen levels stimulate chemoreceptors, baroreceptors are not primarily sensitive to oxygen. Their function is focused on detecting pressure changes rather than gas concentrations.
B. Changes in arterial pressure: Baroreceptors in the carotid sinus and aortic arch detect stretch in the arterial walls caused by increases or decreases in blood pressure. This information is sent to the cardiovascular center to regulate heart rate and vessel tone, making them pressure-sensitive sensors.
C. An increase in oxygen levels: High oxygen levels do not directly affect baroreceptor activity. Baroreceptors respond to mechanical stretch, not oxygen concentration, so oxygen changes are irrelevant to their primary function.
D. A decrease in carbon dioxide: Carbon dioxide levels primarily influence chemoreceptors, not baroreceptors. While CO₂ can indirectly affect cardiovascular responses, baroreceptors themselves do not respond to changes in CO₂.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
A. Interfere with viral replication within cells:Interferons are signaling proteins released by virus-infected cells. They induce neighboring cells to produce antiviral proteins that inhibit viral replication, providing an early defense mechanism against viral infections.
B. Are virus-specific, so that an interferon produced against one virus could not protect cells against another virus:Interferons are not virus-specific. They provide broad antiviral protection by inducing general antiviral states in cells, making them effective against multiple types of viruses.
C. Are routinely used in nasal sprays for the common cold:Interferons are not routinely used as nasal sprays for the common cold due to side effects and limited effectiveness in treating mild viral infections. Their use is primarily therapeutic in serious viral infections or certain cancers.
D. Act by increasing the rate of cell division:Interferons do not stimulate cell division. Instead, they modulate immune responses and activate antiviral defenses, including the production of proteins that inhibit viral replication.
Correct Answer is D
Explanation
A. IgG:IgG is the most abundant antibody in circulation and is primarily involved in secondary immune responses. It appears later in the primary response after IgM and provides long-term immunity and memory.
B. IgE:IgE is involved in allergic reactions and defense against parasitic infections. It is not the first antibody produced during a primary immune response to most pathogens.
C. IgA:IgA is mainly found in mucosal surfaces, such as the respiratory and gastrointestinal tracts, and provides local immunity. It is not the predominant antibody of the primary systemic response.
D. IgM:IgM is the first antibody produced during a primary immune response. It is effective at forming antigen-antibody complexes and activating complement, providing immediate early defense until IgG is produced.
E. IgD:IgD is primarily found on the surface of immature B cells and functions in B cell activation. It is not released in significant amounts during a primary immune 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.