LOCAL ENVIRONMENT ISSUE:
People dump a lot of trash in the sea, and the sea creatures living there goes through a lot of trouble to live with all the muck getting in them. Of course, don't write it like that in your assignment - you'll get told off for the straight forwardness.
Palisade mesophyll cells are closely packed to absorb the maximum light. They are at right angles to the surface of leaf to reduce the number of cross walls. Large vacuole pushes chloroplasts to the edge of a cell. Chloroplasts at edge enable short diffusion path for carbon dioxide and to absorb maximum light.
Hope this helped
