Which of the following describes a characteristic of cancer cells?

A. Defibrillation is used to treat life-threatening arrhythmias such as ventricular fibrillation or pulseless ventricular tachycardia, where the heart is in a chaotic rhythm without an effective contraction.

B. This procedure is performed to relieve significant blockages in coronary arteries that are causing myocardial ischemia or infarction. While coronary artery disease can contribute to cardiac issues, it is not the primary intervention for treating atrial fibrillation with a rapid ventricular response and associated symptoms like dizziness, shortness of breath, and hypotension.
C. While an echocardiogram may be useful in assessing the overall cardiac function and structure, it is not an immediate intervention for the acute management of atrial fibrillation with a rapid ventricular response and unstable symptoms.
D. Synchronized cardioversion is a procedure used to convert certain types of rapid arrhythmias, including atrial fibrillation, to a normal sinus rhythm by delivering a synchronized electrical shock to the heart at a specific point in the cardiac cycle.

A. Cancer cells typically lose their specialized functions and characteristics that normal cells have. This loss of differentiation is known as dedifferentiation, where cancer cells become less specialized and more primitive in nature. This allows them to proliferate rapidly and invade surrounding tissues.
B. Contact inhibition refers to the normal process where cells stop dividing when they come into contact with neighboring cells. In cancer cells, this mechanism is disrupted, leading to uncontrolled cell growth and proliferation. Cancer cells continue to divide and grow even when they are in close contact with other cells, which contributes to tumor formation and progression.
C. Cancer cells often acquire mutations that impair their ability to repair DNA damage effectively. This can lead to an accumulation of genetic mutations over time, which is a hallmark of cancer development. While some cancer cells may still have mechanisms to repair DNA damage, they are often less efficient compared to normal cells, leading to genomic instability and further mutation accumulation.
D. Normal cells follow a tightly regulated cell cycle with specific checkpoints that ensure orderly progression through phases such as G1, S, G2, and M phases. In contrast, cancer cells often have dysregulated cell cycle control. They may bypass checkpoints that normally control cell division, leading to uncontrolled proliferation and growth.