Structure and Function of Cyphellae and cephalepodia in Lichens

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 Structure and Function of Cyphellae and cephalepodia in Lichens  

  Cyphellae (photobionts) are smooth- surfaced depression in the thallus of lichen and are responsible for exchange of the gases. A minute, rimmed, cup-like depression or pore, found in lichens of the genus Sticta, which is visible in the lower surface of the thallus as a small white pit.

              cephalepodia (Mycobiont)  A number of lichens have an alga as the major photobiont but with a cyanobacterium present as a minor photobiont in discrete pockets and such pockets are called cephalepodia. 


The basic structure of a lichen is like that of the popular peanut butter cup candy. A layer of photobionts (the peanut butter) is held within a matrix of fungal fibers or hyphae (the chocolate). This allows the photobionts access to sunlight as well as protection from drying out.

https://educationtechbysapna.blogspot.com/2024/03/glyoxysome-and-its-function.html

Cyphellae are rounded pores that are characteristic of the foliose genus Sticta (Fig. 83). They develop as little rounded pits in the lower surface of the thallus. The lower cortex extends as an encircling protruding rim, enclosing a small craterlike depression. At the bottom of the crater the texture of the tissue is looser, the hyphae becoming separated to form a layer of globose cells (Fig. 90). This structure is similar to that of the lenticels of higher plants. The cyphellae may enlarge and become much bigger and irregular in outline. Old cyphellae lose their function as the rounded cells adhere and are embedded in the gelatinized remnants of the dying outer cells 



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