Answer
1. Division of labor because of specialised tissues that were developed by the process of cell differentiation
2. Surface area to volume ratio becomes smaller in multicellular organisms
Work Step by Step
1. This is where specialized cells carry out the same function and becomes more efficient. These cells will also develop an ideal structure with enzymes needed to carry out specific chemical reactions related to its function. For example, Caenorhabditis elegans (C. elegans) is a multicellular organism that consists of neurons or nerve cells. These types of specialized cells are specifically responsible for the process and transmission of information.
2. Large organisms that consist of many cells has a small surface area to volume ratio and therefore the rate in which materials are transported in and out of the cell is manageable. If this surface area to volume ratio is too large, the rate in which the cell takes in materials or excrete waste will not be quick enough.