VEGETATIVE STRUCTURE OF MUCOR :
The vegetative body of Mucor is eucarpic which consists of white, delicate thread-like cottony cocnocytic much- branched mycelium. The mycelia ramify all over the substratum. The individual thread or unit of the mycelium is known as hypha. Hyphae are colourless or brownish in colour. The septa are developed in the mature hyphae and at the time of the formation of reproductive structures. Mucor consists of three kinds of hyphae: prostrate, sub terranean and aerial.
I.Prostrate: These hyphae spread over the substratum and their branches grow inside the substratum,from where they absorb nutrients.
II.Sub-terranean: These hyphae are much branched and finer than the prostrate hyphae. They penetrate the substratum and help in fixation and absorption of soluble food.
III. Aerial: These hyphae are borne singly from the prostrate mycelium. They are also called sporangiophores which bear sporangia at their tips for asexual reproduction.
The hyphae of the mycelium are coenocytic as they appear in a multinucleated structure due to the lack of cross septum. The cell wall of the hyphal cell is made up of chitin or fungus cellulose. Many other substances such as lipids, proteins, other polysaccharides purines, pyrimidines, Ca++ and Mg+ are also present in the cell wall. Inner to the cell wall, a cell membrane is present that covers the protoplast. The protoplast is granular and forms a peripheral layer inside the cell. The protoplast can be divided into nuclei, cytoplasm and vacuole. There are numerous irregular vacuoles in the cell that make the cell vacuolated. In the cytoplasm, cell organelles such as mitochondria, golgi complex, endoplasmic reticulum, ribosomes etc. are present. Each hyphal cell contains numerous smaller nuclei. The reserve food material is in the form of oil globules and glycogen is found in the cytoplasm.