Lung cancer cells dividing, coloured scanning electron micrograph (SEM). Lung cancer occurs when abnormal cells divide in a chaotic and uncontrolled manner resulting in the formation of a tumour in the lungs. Lung cancer is the most common cause of cancer death in the UK. Here, two daughter cells can be seen. The cells are undergoing cytokinesis, the physical process of cell division which divides the parental cell into two daughter cells. At the end of cytokinesis the two daughter cells remain connected by the midbody for a short time. The midbody is organized by a set of microtubules and its main function is to localize the site of natural detachment (abscission) between the two daughter cells. The cell on the right appears to be displaying extensive blebbing. Blebbing is a bulge or protrusion of the plasma membrane of the cell which is visible on the cell surface. Blebbing is often seen during programmed cell death (apoptosis) or may be seen when a cell is undergoing physical or chemical stresses. Magnification: x4000 when printed at 10 cm wide