Fungi Flashcards
Layers of Fungi Cell Wall
Chitin is right above plasma membrane. Beta 1,3 glucan and then Beta 1,6 glucan woven together on top of chitin. Upper layer of glycoproteins and polysaccharides.
What percent of cell wall is polysaccharides
80-90%
Cell Membrane
Cell membrane similar to animal and plant cells - has ergosterol (6% of membrane composition) rather than cholesterol
It allows regulation of osmotic pressure and good in varying environments.
Evolutionary advantage - ergosterol is seen in all fungi
3 types of Fungi
Yeast
Moulds/Mycelial
Mushrooms
Fungi are heterotrophic - they are either
Saprophytic - feed of dead organic matter
Or
Parasitic - lives inside or outside alive host
Yeasts size
3 -30um
Yeast shape and cell organisation
Spherical, oval and cylindrical
Unicellular
Reproduction
Sexually - spores
Asexually - Budding
Mould structure
Filamentous - they have large branched/thread like filaments called hyphae. Hyphae become compacted to form mycelium.
Mould nuclei
Hyphae have many nuclei due to many cells interconnecting to form the hyphae
Septate Hyphae
Have septums seperating each cell. Large pores between each septum so cell contents can be exchanged easily
Coenocytic Hyphae
They have no septums between cells and contents are free to move through a huge combined cytoplasm
Mushrooms
Fruiting body of the mushroom and only grows when conditions are perfect. Mycelium grows under ground and provides it with water. They release the spores into the surrounding area
Life span of mushroom vs mycelium
Mushroom is short lived but mycelium can survive underground for a long time
Dimorphism
Fungi can change from being a yeast to being a mycelium. This is due to temperature. Mycelium in the cold and yeast in the warmth