What is the principal cation of the ECF?
Na+
Ca2+
CL-
K+
The Correct Answer is A
A. Na+: Sodium (Na+) is the principal cation in the extracellular fluid (ECF), which includes interstitial fluid and blood plasma.
B. Ca2+: Calcium (Ca2+) is important in various bodily functions but is not the principal cation in the ECF. Sodium is more predominant in ECF.
C. Cl-: Chloride (Cl-) is the principal anion in the ECF, not a cation. Sodium is the principal cation.
D. K+: Potassium (K+) is the principal cation in the intracellular fluid (ICF), not the ECF. Sodium is the principal cation in the ECF.
Free Nursing Test Bank
- Free Pharmacology Quiz 1
- Free Medical-Surgical Quiz 2
- Free Fundamentals Quiz 3
- Free Maternal-Newborn Quiz 4
- Free Anatomy and Physiology Quiz 5
- Free Obstetrics and Pediatrics Quiz 6
- Free Fluid and Electrolytes Quiz 7
- Free Community Health Quiz 8
- Free Promoting Health across the Lifespan Quiz 9
- Free Multidimensional Care Quiz 10
View Related questions
Correct Answer is B
Explanation
A. Ductus venosus and ductus arteriosus: The ductus venosus bypasses the liver, not the lungs. The ductus arteriosus does allow blood to bypass the lungs by connecting the pulmonary artery to the aorta. However, this option is not entirely correct since the ductus venosus is not involved in bypassing the lungs.
B. Foramen ovale and ductus arteriosus: The foramen ovale allows blood to pass directly from the right atrium to the left atrium, bypassing the lungs. The ductus arteriosus connects the pulmonary artery to the aorta, also bypassing the lungs.
C. Fossa ovalis and umbilical arteries and vein: The fossa ovalis is a remnant of the foramen ovale in adults and does not function in fetal circulation. The umbilical arteries and vein are involved in exchanging oxygenated and deoxygenated blood between the fetus and placenta, not bypassing the lungs.
D. Ligamentum venosum and ligamentum arteriosum: These are the adult remnants of the ductus venosus and ductus arteriosus, respectively. They do not play a role in fetal circulat
Correct Answer is C
Explanation
A. The neural tube and yolk sac have formed: By 8 weeks, the neural tube and yolk sac have formed, but this is not the criterion for defining a fetus.
B. The amniotic cavity has formed: The formation of the amniotic cavity occurs earlier in development and is not the defining feature of a fetus.
C. All of the organ systems are present: By the end of 8 weeks, the basic structures of all major organ systems are present, which is why the embryo is referred to as a fetus from this point onwards.
D. The mesoderm has formed: The formation of the mesoderm occurs earlier and is not the defining factor for fetal status. By 8 weeks, more significant development, including the presence of organ systems, has occurred.