Which step in the apoptotic sequence occurs as the second observable change?

Which step in the apoptotic sequence occurs as the second observable change?

• A. Plasma membrane blisters and blebs form
• B. The cell fragments are consumed by white blood cells
• C. Chromatin condenses and nucleus fragments
• D. Cell rounds and nucleus collapses

Answer: (C)

In apoptosis, visible changes unfold in a defined order as the cell dismantles itself. After the cell begins to shrink and round up, the next observable change is the condensation of chromatin and fragmentation of the nucleus. This happens because specialized enzymes cut DNA and tighten the chromatin, making the nucleus appear dense and then break apart into fragments. Only after this nuclear remodeling do you see plasma membrane blebbing and the formation of apoptotic bodies, which are eventually cleared by phagocytes. So the second observable change is that chromatin condenses and the nucleus fragments.

In apoptosis, visible changes unfold in a defined order as the cell dismantles itself. After the cell begins to shrink and round up, the next observable change is the condensation of chromatin and fragmentation of the nucleus. This happens because specialized enzymes cut DNA and tighten the chromatin, making the nucleus appear dense and then break apart into fragments. Only after this nuclear remodeling do you see plasma membrane blebbing and the formation of apoptotic bodies, which are eventually cleared by phagocytes. So the second observable change is that chromatin condenses and the nucleus fragments.