Which of the following is an accurate description of a type-1 hypersensitivity reaction?
Most type-1 reactions are allergic
It is mediated by IgA.
It never contributes to autoimmune diseases.
Most occur against medications
The Correct Answer is A
A. Most type-1 reactions are allergic: This statement is accurate. Type-1 hypersensitivity reactions are typically associated with allergies. When a person is exposed to a specific allergen (like pollen or certain foods), their immune system overreacts, leading to various symptoms, from mild to severe.
B. It is mediated by IgA: This statement is incorrect. Type-1 hypersensitivity reactions are primarily mediated by immunoglobulin E (IgE) antibodies. When these antibodies bind to allergens, they trigger the release of histamine and other chemicals, causing allergic symptoms.
C. It never contributes to autoimmune diseases: This statement is incorrect. While type-1 hypersensitivity reactions are often associated with allergies, they are distinct from autoimmune diseases. In autoimmune diseases, the immune system mistakenly attacks the body's own cells and tissues, which is a different mechanism from hypersensitivity reactions.
D. Most occur against medications: This statement is not entirely accurate. While some type-1 hypersensitivity reactions can be triggered by medications (like penicillin), they can also be caused by various other allergens such as pollen, animal dander, insect venom, and certain foods. The prevalence of medication-induced type-1 reactions varies, and it's not accurate to say that most occur against medications.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
A. "Cephalosporins are assigned to generations based on their relative costs to administer."
This statement is incorrect. The classification of cephalosporins into generations is based on their antimicrobial spectrum and activity against specific bacteria, not their cost.
B. "Later generations of cephalosporins have lower resistance to destruction by beta-lactamases."
This statement is not accurate. In fact, later generations of cephalosporins have increased resistance to destruction by beta-lactamases, which are enzymes produced by bacteria that can break down certain antibiotics.
C. "Cephalosporins have increased activity against gram-negative bacteria with each new generation."
This statement is correct. Cephalosporins are grouped into generations (first to fifth) based on their antibacterial spectrum. As the generations progress, there is an increase in activity against gram-negative bacteria, among other improvements in their spectrum.
D. "First-generation cephalosporins have better penetration of the cerebrospinal fluid."
This statement is generally true. First-generation cephalosporins have better penetration into the cerebrospinal fluid, making them useful for treating certain central nervous system infections.
Correct Answer is A
Explanation
A. "Tetracycline inhibits protein synthesis."
Tetracycline inhibits bacterial protein synthesis by binding to the bacterial ribosomes, which are crucial for making proteins. This disruption in protein synthesis prevents bacterial growth and replication.
B. "Tetracycline blocks RNA synthesis."
Tetracycline primarily affects protein synthesis, not RNA synthesis. It binds to the 30S subunit of the bacterial ribosome and disrupts the translation process.
C. "Tetracycline degrades the bacterial cell wall."
Tetracycline does not target the bacterial cell wall. Drugs like penicillin and cephalosporins work by disrupting cell wall synthesis, but tetracycline operates differently by inhibiting protein synthesis.
D. "Tetracycline binds to magnesium ions."
Tetracycline does not specifically bind to magnesium ions. Its primary mode of action involves binding to the bacterial ribosome, as mentioned in the first correct statement.
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