Pit connection
In
Characteristics
A sieve-like membrane may cover the pit in living algae,[4] but in the majority of algae a plug forms, they likely limit the transfer of metabolites between neighbouring cells.[2][5]
Formation
Primary pit connections are formed between cells in the same filament, derived from the same parent cell by its division.[4] Such connections are always single, and usually circular;[4] this is a result of their method of formation. The septum is formed as the walls of a filament grow inwards, dividing the cell; this results in a hole in the middle of the tube where the walls don't quite merge.[2] Thus pit connections are visible in the youngest of septa, widening as the septum thickens, until in some cases they may ultimately occupy the entire septum.[4] Secondary connections, by contrast, occur between unrelated cells, and serve a role in transferring cell contents and nutrients.[2] They may even form between cells of different species, as in the parasite Holmsella.[6]
References
- JSTOR 2439535.
- ^ ISBN 978-0-521-63883-8
- JSTOR 3758285.
- ^ OCLC 223742770
- S2CID 21177509.
External links
- Transverse SEM images of pit connections in the coralline
- (Lower quality) transverse SEM images of pit connections in the coralline ..