Sporulation (spore formation) in Rhizopus
Rhizopus is a saprophytic fungus which grows on a substrate like bread.
The vegetative body is called mycelium which consists of many branched threads called hyphae.
The horizontal hyphae are called stolons.
The hyphae which grow vertically are called sporangiophores.
The tips of these upright hyphae swell up to form the sporangia (spore-producing structures).
Inside the sporangium, the nuclei divide meiotically producing daughter nuclei that contain a haploid number of chromosomes (n).
The daughter nuclei develop into spores by the incorporation of the cytoplasm around each nucleus and a wall around the cytoplasm.
The sporangium contains many spores, as it matures and ripens, it turns black in colour.
When fully mature, the sporangium wall burst and release the spores, which are dispersed to restart a fresh generation of growth and development.
Spore dispersal may be by wind, insects or animals.
