Parenchyma cells are spherical or polygonal in shape. Sometimes they may be elongated and columnar as in the leaves. Studies based on geometric models have indicated that closely packed parenchyma cells have the shape of a polyhedron with approximately fourteen faces. Parenchyma cells are closely packed or arranged loosely with large number of intercellular spaces.
Cell structure:
The cells have thin walls and have dense cytoplasm with a prominent nucleus. Parenchyma cells in storage organs have abundant reserve food materials like proteins, fats and carbohyderates. Parenchyma cells found in leaves has number of choloroplasts. These helps in photosynthesis.