How it Works
Try Naxlex NCLEX-RN (Free-Trial)

Which of the following is an essential role of calcium?

A.

Blood clotting

B.

Acid buffering

C.

Extracellular osmotic pressure

D.

ATP production

Answer and Explanation

The Correct Answer is A

A. Calcium plays a critical role in blood clotting. It is involved in the coagulation cascade and is necessary for the activation of clotting factors that help stop bleeding. 

B. Calcium is not involved in acid buffering. This function is primarily carried out by buffers such as bicarbonate in the blood. 

C. While calcium does help regulate some functions of cells and tissues, it does not primarily contribute to extracellular osmotic pressure; this is more a function of proteins and other ions. 

D. ATP production mainly occurs in mitochondria and is driven by the metabolism of glucose and fatty acids, not by calcium directly. Calcium does, however, play a role in cellular processes like muscle contraction.


Get 100+ Naxlex Exit Exams for $79 Try Naxlex NCLEX-RN (14 Day Free-Trial)

Naxlex Comprehensive Predictor Exams

Free Nursing Study Resources

Related Questions

Correct Answer is C

Explanation

A. As previously noted, the length of the thoracic cavity increases, not decreases, during the contraction of inspiratory muscles.

B. The diaphragm moves downward (not upward) when it contracts, allowing the lungs to expand.

C. The contraction of the diaphragm and external intercostals increases the diameter of the thoracic cavity, providing space for the lungs to expand and fill with air. This is the correct answer.

D. The chest cavity does not compress the lungs during inspiration; instead, it expands to accommodate the lungs as they fill with air.

Correct Answer is D

Explanation

A. Expiratory reserve volume is the amount of air that can be exhaled forcefully after normal expiration. It does not refer to the air moved in and out during the normal respiratory cycle.

B. Residual volume is the amount of air remaining in the lungs after a forced exhalation. It cannot be exhaled and is not part of the normal respiratory cycle.

C. Vital capacity is the maximum amount of air that can be exhaled after a maximum inhalation, which includes tidal volume, expiratory reserve volume, and inspiratory reserve volume. It does not specifically refer to the air moved in and out during normal breathing.

D. Tidal volume refers to the amount of air that is moved into and out of the lungs during a normal, relaxed breath. It is the term that directly describes the air exchanged during the normal respiratory cycle.

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

Register