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
Veins are the type of blood vessel that holds the greatest volume of blood and serve as reservoirs for blood.
According to 1, veins contain about 70-80% of the blood volume in circulation.
Veins are also called capacitance vessels because they can expand and store more blood when needed.
Choice A. Capillary is wrong because capillaries are very thin and narrow vessels that allow the exchange of gases and nutrients between the blood and the tissues.
Capillaries have a very small volume compared to veins.
Choice C. Arteriole is wrong because arterioles are small branches of arteries that regulate blood pressure and blood flow to the capillaries.
Arterioles have a higher resistance and lower volume than veins.
Choice D. Artery is wrong because arteries are thick and muscular vessels that carry oxygen-rich blood away from the heart to the rest of the body.
Arteries have a higher pressure and lower volume than veins.
Normal ranges for blood volume vary depending on age, sex, weight, and health status, but generally range from 4 to 6 liters for adults.
Correct Answer is A
Explanation
Red blood cells do not contain a large nucleus; in fact, they do not contain a nucleus at all when they are mature.
This is an adaptation that allows them to carry more hemoglobin, the protein that binds oxygen, and to squeeze through narrow capillaries.
Choice B is wrong because it contradicts the fact that red blood cells are enucleated (lacking a nucleus) in humans and most mammals.
Some vertebrates, such as birds and fish, have nucleated red blood cells, but they are not thick near the center and thin around the rim of the cell.
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