What are the challenges of be multicellular?

Answer 1

Multicellular organisms have unique survival issues depending on their habitats. Terrestrial animals must conserve water, and thus have evolved to secrete concentrated urea. Vice-versa marine animals do the opposite.

Answer 2

Let us take the Amoeba as an example. The general principles will apply to most unicellular organisms.

1. The minute physical size makes the unicellular organism prey to larger organisms

2. Dessication: because the habitat of a freshwater Amoeba is strictly limited, should its environment dry up, then the Amoeba could die. However, in order to mitigate this, the Amoeba will often enclose itself in a capsule which resists drying out. Within this capsule it will remain dormant for a considerable time. When its environment once more receives a rainfall then the capsule breaks down and releases the Amoeba

3. Osmosis: Should the concentration of material within the Amoeba be greater than the concentration of the medium in which it lives, there is an osmotic tendency for the fluid in the environment to seep through the semi-permeable membrane of the Amoeba. So, to prevent its destruction by this effect, the Amoeba possesses a CONTRACTILE VACUOLE, that is a sac which bursts open now and again, thus releasing the build up of fluid.

That should be enough to think about for now

Answer 3

Because mulitcellular organisms have many layers of cells, it is difficult to transport and exchange materials and nutriments from the environment to every cell of the body

Answer 4

If you're multicellular, you need to get more food because you're feeding many cells. Also, you create more waste because your cells are all doing cellular respiration.