a thin piece of wood or other rigid material used to immobilize a fractured or dislocated bone, or to maintain any part of the body in a fixed position. 2. one of a number of thin strips of wood woven together to make a chair seat, basket, etc.
If you take a close look at epithelial cells using a microscope, you will see them tightly packed together. This helps make a protective barrier for our bodies. There are also some special door-like connections between each epithelial cell called gap junctions. The gap junctions are where the cells exchange nutrients.
Gas exchange happens in the spongy mesophyll tissue of the leaf. Spongy mesophyll cells are covered by a thin layer of water and loosely packed. When the plant is photosynthesising during the day, these features allow carbon dioxide to diffuse into the spongy mesophyll cells, and oxygen to diffuse out of it.pongy mesophyll cells are covered by a thin layer of water and loosely packed. When the plant is photosynthesising during the day, these features allow carbon dioxide to diffuse into the spongy mesophyll cells, and oxygen to diffuse out of it.