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. Delayed hypersensitivity reaction: This type of hypersensitivity reaction, also known as Type IV hypersensitivity, involves a delayed response by the immune system and is mediated by T cells. It does not necessarily involve a failure of self-tolerance.
B. Antibody-mediated reaction: This type of hypersensitivity reaction, also known as Type II hypersensitivity, involves antibodies targeting specific antigens on cell surfaces, leading to cell destruction. It doesn't directly indicate a failure of self-tolerance but rather an immune response against specific cells or tissues.
C. Autoimmune reaction: In autoimmune reactions, the immune system fails to recognize certain body tissues or substances as "self," leading to an immune response against the body's own cells or tissues. This results from a breakdown in self-tolerance, where the immune system mistakenly targets its own body.
D. Immediate hypersensitivity reaction: This type of hypersensitivity reaction, also known as Type I hypersensitivity, involves an immediate response by the immune system to an allergen. It includes conditions like allergies and anaphylaxis, where the immune system reacts strongly to substances that are normally harmless. This response does not necessarily indicate a failure of self-tolerance but rather an exaggerated response to specific antigens.
Correct Answer is B
Explanation
A. Gut-associated lymphoid tissue (GALT): GALT is a component of the mucosa-associated lymphoid tissue (MALT) and refers to the immune cells found in the gastrointestinal tract. These cells play a significant role in local immune responses in the gut.
B. Bone marrow: The bone marrow is the primary site of blood cell production in the body. It contains stem cells that can differentiate into various blood cells, including B cells. B cells mature in the bone marrow.
C. Thymus: The thymus is an organ located near the heart and is crucial for the development of T cells. T cells mature in the thymus, where they learn to recognize self from non-self antigens.
D. Lymph nodes: Lymph nodes are small, bean-shaped structures that produce and store cells that help fight infection. While they are essential parts of the immune system, B and T cells are not originally derived from lymph nodes.
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