Which of the following waves represents the ventricular depolarization on ECG?
QRS wave
P wave
T wave
U wave
The Correct Answer is A
a. QRS wave: The ECG (electrocardiogram) measures the electrical activity of the heart. The QRS complex represents ventricular depolarization, the spread of electrical excitation through the ventricles causing them to contract.
b. P wave: The P wave represents atrial depolarization, the electrical impulse moving through the atria.
c. T wave: The T wave represents ventricular repolarization, the ventricles relaxing after contraction.
d. U wave: The U wave is a small wave of uncertain origin, not related to ventricular depolarization.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is D
Explanation
a. Activation of plasmin: Plasmin is involved in breaking down blood clots, not in their formation. It is part of the fibrinolytic system.
b. Activation of heparin: Heparin is an anticoagulant that prevents clotting; it is not required for blood clotting.
c. Adequate levels of potassium: Potassium is important for cellular function but does not play a direct role in blood clotting.
d. Adequate levels of calcium: Calcium ions are essential for various steps in the blood clotting cascade, including the activation of certain clotting factors.
Correct Answer is A
Explanation
a. Insulin and glucagon: These hormones have opposite effects on blood glucose levels; insulin decreases blood glucose by facilitating cellular uptake, while glucagon increases blood glucose by stimulating glycogen breakdown and gluconeogenesis.
b. Ghrelin and gastrin: Ghrelin stimulates appetite, and gastrin stimulates gastric acid secretion, but they do not directly oppose each other.
c. Calcitonin and melatonin: Calcitonin lowers blood calcium levels, while melatonin regulates sleep-wake cycles; they do not act as antagonists.
d. Androsterone and estradiol: These are sex hormones with different roles but are not direct antagonists; they do not have opposing effects in the body.
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