The loose-fitting sac around the heart is the:
Fibrous pericardium.
Epicardium.
Endocardium.
Visceral pericardium.
The Correct Answer is A
The fibrous pericardium is the loose-fitting sac around the heart that protects it and anchors it to surrounding structures.
Choice B is wrong because the epicardium is the outer layer of the heart wall, also called the visceral pericardium, and it is not a sac.
Choice C is wrong because the endocardium is the inner layer of the heart wall that forms the lining of all heart chambers, and it is not a sac.
Choice D is wrong because the visceral pericardium is another name for the epicardium, and it is not a loose-fitting sac.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is B
Explanation
T lymphocytes, also known as T cells, are a type of white blood cell that is an essential part of the immune system.
T cells are one of two primary types of lymphocytes — B cells being the second type — that determine the specificity of immune response to antigens (foreign substances) in the body.
T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their cell surface.
T cells originate in the bone marrow and mature in the thymus.
After migration to the thymus, the precursor cells mature into several distinct types of T cells.
One of these types is the CD8+ T cell, also known as cytotoxic T cell, which is responsible for cell-mediated immunity.
Cell-mediated immunity is the type of immunity that involves the direct killing of infected cells and cancer cells by cytotoxic T cells.
Choice A is wrong because humoral immunity is the type of immunity that involves the production of antibodies by B cells and plasma cells.
Antibodies are proteins that bind to specific antigens and mark them for destruction by other immune cells.
Choice C is wrong because programming macrophages is not a function of T lymphocytes.
Macrophages are a type of phagocytic cell that can engulf and digest pathogens and cellular debris.
Macrophages can be activated by cytokines, which are chemical messengers secreted by helper T cells and other immune cells.
Choice D is wrong because producing antibodies is not a function of T lymphocytes.
As mentioned above, antibodies are produced by B cells and plasma cells, which are another type of lymphocyte.
Correct Answer is D
Explanation
This is because blood type AB has both A and B antigens on the surface of red blood cells.
Antigens are protein molecules that can trigger an immune response if they are foreign to the body.
Choice A is wrong because antigen B only is present in blood type B.
Choice B is wrong because neither antigens A nor B are present in blood type O.
Choice C is wrong because antigen A only is present in blood type A.
Normal ranges for blood types vary by population, but according to the NHS, about 3% of people in the UK have blood type AB.
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