As a result of the allergen-antibody reaction, mast cells release histamine:
False
True
The Correct Answer is B
As a result of the allergen-antibody reaction, mast cells release histamine.
This is because when mast cells are exposed to an allergen that binds to IgE antibodies attached to their FcɛRI receptors, they release histamine and other inflammatory mediators.
Histamine causes vasodilation, increased capillary permeability, mucus secretion, and smooth muscle contraction, which result in allergic symptoms such as itching, swelling, sneezing, and wheezing.
Mast cells do release histamine in response to allergen-antibody reactions. Some additional sentences are:
Normal ranges of histamine levels vary depending on the tissue and the method of measurement, but they are usually low in healthy individuals and elevated in allergic conditions.
Histamine can be degraded by enzymes such as diamine oxidase and histamine N- methyltransferase, or inhibited by drugs such as antihistamines.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
It explains that the primary immune response produces antibodies within five to ten days of exposure to antigens, while the secondary immune response produces antibodies within a day or two of subsequent exposure to the same antigen.
This is because the primary immune response involves the activation and differentiation of naive B cells into plasma cells and memory cells, while the secondary immune response involves the rapid activation of memory cells into plasma cells.
Choice A is wrong because the primary and secondary immune responses can occur in both children and adults.
Choice B is wrong because the primary immune response is slower than the secondary immune response in producing antibodies.
Choice D is wrong because both primary and secondary immune responses are important for the body’s ability to protect itself from pathogens.
The primary immune response generates immunological memory, while the secondary immune response provides a faster and stronger response to repeated infections.
Correct Answer is A
Explanation
It is a major component of the lymphatic system and contains T and B lymphocytes.
Choice B is wrong because the spleen does not produce T lymphocytes, but rather stores them.
T lymphocytes are produced in the thymus.
Choice C is wrong because the spleen does not filter lymph, but rather blood. It traps bloodborne microbes and produces an immune response to them.
Choice D is wrong because the spleen consists of one lobe and is located in the upper left abdomen below the diaphragm.
The description in choice D matches the thymus, not the spleen.
The normal size of the spleen in adults is about 12 cm long, 8 cm broad, and 3-4 cm thick, weighing about 200 g.
The normal range of splenic index (the product of length, width, and thickness) is 120-480 cm.
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