Question

explain "dynamic" continuity in endoskeleton and endomembrane system

Answer 1

There are many membrane suspended in the cell’s cytoplasm. Together all these membranes constitute the endomembrane system. These membranes always remain in a dynamic state, i.e. their components keep forming and disintegrating. With each and every successive cell division, DNA replication, transcription and protein synthesis occurs.

Transcription occurs in the nucleus; this results in formation of RNA. RNA moves out of the nuclear pores into the cytoplasm. In the cytoplasm and on the surface of Rough Endoplasmic Reticulum (RER), protein synthesis occurs. The nascent proteins move into the lumen of RER; here they get modified. The proteins of the ER remain here, while the rest of the proteins move towards the golgi apparatus. The cisternae, tubules and vesicles of golgi keep forming and disintegrating.

The vesicles carry the proteins towards the lysosomes and the plasma membrane; these help in forming their enzymes, proteins and the membrane structure.

In this way, the endomembrane always remains dynamic i.e. in a state of motion.

Note: The endoskeleton is a rigid structure. It does not remain in a state of dynamic continuity. It is only the endomembrane system which is in a state of dynamic continuity.