Question

Pyknosis, karyorrhexis and karyolysis indicates that the cell is
(A) Dead
(B) Going to divide
(C) Resting
(D) Activity synthesizing the secretory granules.

Answer 1

Hint: These are sequential changes in the nucleus.

Complete answer:
The meaning of the these terms is as follows:

1. Pyknosis is the process of nuclear shrinkage. It is an irreversible condition of chromatin in the nucleus of a cell wall undergoing necrosis or apoptosis.
2. Karyorrhexis is the destructive fragmentation of the nucleus of a daily cell whereby its chromatin is distributed irregularly throughout the cytoplasm.
3. Karyorrhexis is usually preceded by pyknosis.
4. Karyolysis is a complete dissolution of the chromatin of a dying cell due to enzymatic degradation by endonucleases.
5. Karyolysis occurs after karyorrhexis.
6. In this way these changes lead to destruction of the nucleus.
7. As the nucleus of the cell is being destroyed we can say that the cell is going to die.

So the correct answer is open (A) Dead.

Additional information: - different causes of cell death are as follows:
1) Autophagy
2) Apoptosis
3) Necrosis

Note: All these changes occur in following order:
Pyknosis- nuclear shrinkage
Karyorrhexis- nuclear fragmentation
Karyolysis- nuclear fading