SCIENCE PHOTO LIBRARY. SCIENCE PHOTO LIBRARY.
Light micrograph of numerous squamous cells from the epithelial lining of the vagina, the female birth canal. The sample of cells was removed during the mid-cycle menstrual stage. During the menstrual cycle the stratified squamous epithelium undergoes cyclical changes that includes slight keratinisation of the superficial cells. Here, the cells are of roughly uniform size, with a large cytoplasm and a small, central nucleus. Throughout the cycle the superficial cells produce glycogen, which is metabolised by commensal bacteria (Lactobacillus sp.) to produce lactic acid that inhibits growth of disease-causing microorganisms. Magnification: X 40 at 35mm size.
Model release not required. Property release not required.