Mammal, bovine ovary (LM, Medium)

Structure List Ovum Corona radiata Cumulus oophorus Antrum Basement membrane Theca interna Theca externa Artifact (fold in tissue) Low Magnification View

The granulosa cells are surrounded by a capsule of modified stroma cells known as the theca folliculi. ( The theca folliculi is made up of two layers, the theca interna and theca externa. The theca interna is composed of aggregates of epithelioid cells with lipid droplets in the cytoplasm and surrounded by capillaries. The cells secrete the female sex steroids. The theca externa is made up of concentric layers of spindle-shaped stroma cells.