Ecosystems can be large and are made of biomes. Some examples of ecosystems are deserts and forests.
A glucose molecule is too large to pass through a cell membrane via simple diffusion. Instead, cells assist glucose diffusion through facilitated diffusion and two types of active transport.
So the answer is B
The answer is D its tightly packed cells allow for proctection against harmful substances.
Multicellular organisms are referred to as eukaryotes while the opposite, unicellular organisms, are called prokaryotes. Among all the kingdoms, I believe the kingdom which all organisms are multicellular are Animalia and Plantae.