Ultrastructure of cells

Organelles and cell functions

Pancreatic acinar cells are specialized for the production of digestive enzymes. These cells have a higher rate of protein synthesis than all other adult human tissues. Digestive enzymes are produced in the rough endoplasmic reticulum (rER), a multifunctional organelle responsible for the synthesis and correct folding of proteins in the secretory pathway. The packaging and secretion of digestive enzymes is done by the Golgi Apparatus.

Palisade mesophyll cells are highly differentiated cells that make up the mesophyll layer found in plant leaves. These cells have many chloroplasts making the mesophyll the site of photosynthesis. The main organelles are found in these cells are nucleus, cell membrane, a large vacuole, chloroplasts and the cell membrane. Palisade cells are generally arranged in a vertical manner to each other beneath the leaf epidermis and between the cells there are slight separations that allow various materials to flow (apoplast and symplast pathways, IB Topic 9).