What are the d i s a d v a n t a g e s of multicellularity?

If an organism is made up of more than one cell, then it is known as a muticellular organism. Multicellularity has advantages as well as disadvantages. Following are the disadvantages of multicellularity:

1. A multicellular organism needs more food than unicellular organsism because it needs more energy.
2. In multicellular organisms, cells are organized into tissues and tissues are further organised into organs. So, if one organ fails, then whole organism can fail.
3. In multicellular cells, due to specialization, regeneration ability is very less.
4. In order to carry out specific activities, sometimes specialized cells may lose their vital functions, e.g. RBCs, sieve tube cells.
5. A multicellular organism has more risk from the infection caused by unicellular organisms.