observed as a large factor in substrate penetration. In species such as Saprolegnia ferax, Magnaporthe grisea and Aspergillus oryzae, immense turgor pressures have been observed in their hyphae. The study showed that they could penetrate substances like plant cells, and synthetic materials such as polyvinyl chloride. In observations of this phenomenon, it is noted that invasive hyphal growth is due to turgor pressure, along with the coenzymes secreted by the fungi to invade said substrates. Hyphal growth is directly related to turgor pressure, and growth slows as turgor pressure decreases. In Magnaporthe grisea, pressures of up to 8 MPa have been observed. Protists Some protists do not have cell walls and cannot experience turgor pressure. These few protists use their contractile vacuole to regulate the quantity of water within the cell. Protist cells avoid lysing in hypotonic solution by utilizing a vacuole which pumps water out of the cells to maintain osmotic equilibrium. Animals Turgor pressure is not observed in animal cells because they lack a cell wall. In organisms with cell walls, the cell wall prevents the cell from being lysed by high turgor pressure. Diatoms In diatoms, the Heterokontophyta have polyphyletic turgor-resistant cell walls. Throughout these organisms' life cycle, carefully controlled turgor pressure is responsible for cell expansion and for the release of sperm, but not for processes such as seta growth. Cyanobacteria Gas-vaculate cyanobacterium are the ones generally responsible for water-blooms. They have the ability to float due to the accumulation of gases within their vacuole, and the role of turgor pressure and its effect on the capacity of these vacuoles has been reported in varying scientific papers. It is noted that the higher the turgor pressure, the lower the capacity of the gas-vacuoles in different cyanobacteria. Experiments used to correlate osmosis and turgor pressure in prokaryotes have been used to show how diffusion of solutes into the cell affects turgor pressure within the cell. Measurements When measuring turgor pressure in plants, many factors have to be taken into account. It is generally stated that fully turgid cells have a turgor pressure that is equal to that of the cell and that flaccid cells have a value at or near zero. Other cellular mechanisms to be taken into consideration include the protoplast, solutes within the protoplast (solute potential), transpiration rates of the cell and the tension of cell walls. Measurement is limited depending on the method used,