The development of individual organs involves precise patterning of cells. The regulation of cell growth and division plays a large role in generating this patterning, and a recent paper used the sepal of the plant Arabidopsis thaliana as a model to investigate this. The sepal is the outer green, leaf-like floral organ on the plant, and is made of a distinct pattern of cells with a wide range of sizes. Image above is a scanning electron micrograph of an Arabidopsis sepal with giant cells colored red.
Reference: Adrienne H. K. Roeder, Vijay Chickarmane, Alexandre Cunha, Boguslaw Obara, B. S. Manjunath, Elliot M. Meyerowitz. Authors’ PLoS Biology paper can be found here.