Light micrograph of Rhizopus rot caused by the pathogen Rhizopus stolonifer (black bread mold) in Solanum lycopersicum (tomato fruit). At the top, we can see the sporangium, a spherical structure (the black spheres are mature sporangia, while the white and transparent ones are immature sporangia) with sporangiospores and columella (inside). The sporangiophore is the slender stem (with the apophysis and collarette at the top). This fungus plays a major role in the carbon cycle as a decomposer in the soil. It has the ability to transform steroids such as progesterone. It can cause: zygomycosis in humans, Rhizopus soft rot in sweet potatoes, and disease in many fruits and vegetables. It is a source of cortisone, fumaric acid, and lactic acid. Field of view size: 1.25 x 1.87 mm (0.049 x 0.074 in)